Genetic Determination and Exogenous Influence in Sex Differentiation in Crustacean

The mechanisms of sex determination and the influence of exogenous factors on sex differentiation in crustacean were reviewed in the paper.Most of crustecea have not obviously sex chromosome.Androgenic gland was reported as the most important sex differentiation factors,implanting or cuting AG can change the sexal characterization of larval in crustacean.Although sex differentiation of crustacean is determined by gene,it is affected by exogenous factors such as parasite,photoperiod,temperature or hormone.Most cultured species have different body weight and length between male and female,this can be used in aquaculture to produce all male or female crusteceans to improve the production.

Review of Research on Sex Differentiation in Bitter Gourd(Momordica charantia L.)

Bitter gourd,with its narrow genetic background and rich sexual type,is a preferred material to be used to study the gender differentiation of flower buds of monoecious plants.This article is a review of studies on the gender differentiation of flower buds of bitter gourd,from morphology to cytology,from classical genetics to molecular biology,and the mechanism by which it is regulated.The recent rapid development of whole genome sequencing and high throughput sequencing provides a novel approach to the study of the gender differentiation of flower buds of bitter gourd.The study of the gender differentiation of flower buds of bitter gourd can provide references for the regulation of gender differentiation and molecular breeding of bitter gourd.

A Model of Hormonal and Environmental Involvement in Growth and Sex Differentiation in European Eel (Anguilla Anguilla)

Growth in vertebrates is a complex interaction involving the development of cells, tissues and organs. Hormones regulating growth during maturation are involved mainly in the interaction between the somatic axis and the reproduction of brain-pituitary axes. Based on the results of hormone and gene transcriptions, the secretion and treatment controlling both the somatic axis and the gonadotropic axis were affected, directly or indirectly, by the environment parameter through hormones that were studied in my laboratory. A model was proposed for sex differentiation and gonadal development correlating to the growth of European eel (Anguilla anguilla). A high growth variation is affected by the environment. At a low density of eels, the gonadotropin-releasing hormone (GnRH) affected the secretion follicle stimulation hormone (FSH) in the pituitary, steroidogenesis and aromatase (CYP19) synthesis, and the 17β-estradiol (E2) from 11-ketotestosterone (Kt-11) causing ovary development. The ovary secretion E2 affecting the ade-nylate cyclase-activating polypeptide (PACAP), growth hormone (GH) and the insulin-like growth factor (IGF) stimulated rapid growth in females. On the other hand, a high density of eels caused the pituitary gland to secrete FSH at a lower level, and CYP19 was not synthesized in the gonads. The secretion of Kt-11 affected differentiation to testis, which inhibits the somatic axis in reducing growth rate.

Progressive meristem and single-cell transcriptomes reveal the regulatory mechanisms underlying maize inflorescence development and sex differentiation

Maize develops separate ear and tassel inflorescences with initially similar morphology but ultimately different architecture and sexuality.The detailed regulatory mechanisms underlying these changes still remain largely unclear.In this study,through analyzing the time-course meristem transcriptomes and floret single-cell transcriptomes of ear and tassel,we revealed the regulatory dynamics and pathways underlying inflorescence development and sex differentiation.We identified 16 diverse gene clusters with differential spatiotemporal expression patterns and revealed biased regulation of redox,programmed cell death,and hormone signals during meristem differentiation between ear and tassel.Notably,based on their dynamic expression patterns,we revealed the roles of two RNA-binding proteins in regulating inflorescence meristem activity and axillary meristem formation.Moreover,using the transcriptional profiles of 53910 single cells,we uncovered the cellular heterogeneity between ear and tassel florets.We found that multiple signals associatedwith either enhancedcell death or reduced growth are responsiblefortassel pistil suppression,while part of the gibberellic acid signal may act non-cell-autonomously to regulate ear stamen arrest during sex differentiation.We further showed that the pistil-protection gene SILKLESS 1(SK1)functions antagonistically to the known pistil-suppression genes through regulating common molecular pathways,and constructed a regulatory network for pistil-fate determination.Collectively,our study provides a deep understanding of the regulatory mechanisms underlying inflorescence development and sex differentiation in maize,laying the foundation for identifying new regulators and pathways for maize hybrid breeding and improvement.

Impact of xenoestrogens on sex differentiation and reproduction in teleosts

Among vertebrates,teleosts display a wide array of sex determination and differentiation mechanisms ranging from chromosomal sex determination on one end of the spectrum to environmental sex determination on the other end.However,the interplay of both these mechanisms is also not uncommon.Several gonochoristic fishes exhibit gonadal plasticity often resulting in sex reversal.The major manipulation of sex differentiation in teleost is affected by sex steroids.In this context,the increasing contamination of aquatic ecosystems by estrogen-like compounds,commonly known as xenoestrogens,is of major concern.This often leads to deleterious effects on the reproductive success of fish and thereby adversely impacts aquatic biodiversity.In the present review,we have focused on impact of xenoestrogen at different levels of the reproductive system influencing not only gonadal differentiation in teleosts but also their reproductive functions.The review would also explore the mitigation strategies and regulations in place for aquatic xenoestrogen management.

A Review of Sexual Determination and Differentiation in Crustacean

The prerequisite for monosex culture is to elucidate the molecular mechanism of sex determination and differentiation in crustaceans, as well as to explore the key genes that play a role in this process. Monosex culture technology based on crustacean economic species is of great importance in terms of genetic breeding and economic benefits of aquaculture. As a result, study into the mechanisms of sex determination and differentiation in crustaceans not only contributes to the current absence of basic theories of crustacean sexual mechanism, but also encourages technical innovation in aquaculture to increase overall economic efficiency. This study synthesizes and evaluates available research on sex determination and differentiation in crustaceans, and then provides recommendations for future research objectives and priorities in the field.

A landscape of differentiated biological processes involved in the initiation of sex differentiation in zebrafish

Zebrafish(Danio rerio)has been used as a promising animal model to study gonadal development and gametogenesis.Although previous studies have identified critical molecules participating in zebrafish gonad differentiation,a landscape view of the biological processes involved in this process is still lacking.Here we isolated intact zebrafish differentiating gonads,at 25 days post-fertilization(dpf)and 30 dpf and conducted RNA-seq analyses on the juvenile gonads that tended to develop into ovaries or testes.Our study demonstrates that the juvenile ovary and testis at 25 dpf and 30 dpf are different at the biological process level.During ovary differentiation,the biological processes related to metabolic activities in the production of energy and maternal substances,RNA degradation,and DNA repair were enriched.During testis differentiation,the biological processes related to cell proliferation,differentiation,and morphogenesis were enriched,with a total of 15 signaling pathways.Notably,we reveal that the immune-related processes are extensively involved in the regulation of testis development.Overall,this study provides a landscape of differentiated biological processes and novel insights into the initiation of sex differentiation in zebrafish.

Spatial transcriptomics combined with single-nucleus RNA sequencing reveals glial cell heterogeneity in the human spinal cord

Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative disorders.Glial cells include astrocytes,microglia,and oligodendrocytes in the central nervous system,and satellite glial cells and Schwann cells in the peripheral nervous system.Despite the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RNA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal cord.Here,we used high-throughput single-nucleus RNA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal cord.To explore the conservation and divergence across species,we compared these findings with those from mice.In the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic subclusters.In the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,respectively.The comparative results revealed substantial heterogeneity in all glial cell types between humans and mice.Additionally,we detected sex differences in gene expression in human spinal cord glial cells.Specifically,in all astrocyte subtypes,the levels of NEAT1 and CHI3L1 were higher in males than in females,whereas the levels of CST3 were lower in males than in females.In all microglial subtypes,all differentially expressed genes were located on the sex chromosomes.In addition to sex-specific gene differences,the levels of MT-ND4,MT2A,MT-ATP6,MT-CO3,MT-ND2,MT-ND3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in males.Collectively,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for exploring the cellular basis of spinal cordrelated illnesses,including chronic pain,amyotrophic lateral sclerosis,and multiple sclerosis.

Identification and Characterization of Long Non-Coding RNAs Involved in Sex-Related Gene Regulation in Kelp Saccharina japonica

Long non-coding RNAs(lncRNAs)regulate a variety of biological processes,including sexual reproduction and differentiation.Saccharina japonica,a commercially important brown alga in China,shows remarkable sexual dimorphism in haploid gametophytes.The sex of Saccharina japonica gametophytes is determined by UV sexual system.However,no results have been reported on the lncRNAs involved in the sex-related gene regulation of S.japonica.This study identified a number of lncRNAs and assessed their expression levels in male and female gametophytes.Among them,a total of 405 lncRNAs and 211 mRNAs showed differential expressions.Furthermore,the functions of target genes of differentially expressed lncRNAs(DELs)differed from those of differentially expressed genes(DEGs),suggesting that lncRNA may interact with other functional proteins,in addition to DEGs,to involve sex regulation in S.japonica.There were 32 and 90 potential cis-regulatory and trans-regulatory interactions between DELsDEGs,respectively.Five of these lncRNAs(LNC_002974,LNC_021059,LNC_038466,LNC_051584,and LNC_027400)interacted with putative male sex determination region(SDR)genes,suggesting that they act as regulators in gametophytes'sex regulation potentially.Findings from this study contribute to our understanding of the roles of lncRNAs in sex differentiation and lay the foundation for functional studies of candidate lncRNAs in the future.

Sex determination and dif ferentiation in Aurelia sp.1: the absence of temperature dependence

Cnidarians, being regarded as ‘basal' metazoan animals, are considered to have relatively high plasticity in terms of sex reversal. In this study we used an experimental approach to demonstrate sexual diff erentiation and plasticity in benthic polyps and pelagic medusae of A urelia sp.1 maintained at dif ferent temperatures. Results indicated that in A urelia sp.1, sex diff erentiation has been determined at the polyp stage and that all medusae originating from a given polyp are, phenotypically, of the same sex. In addition, the sex of polyps budding from the same clone(either male or female) at dif ferent temperatures appears to be the same as that of the parent. The sex of medusae that had originated from a known-sex polyp was observed to remain the same as that of the parent, irrespective of differences in strobilation or rearing temperatures. These results indicate that the mechanism of sex determination of Aurelia sp.1. is not influenced by prevailing temperature regimes. A comparison of variability in terms of sexual plasticity of A urelia sp.1 with that of Hydrozoa and Anthozoa suggests that species characterized by a free-swimming medusa life stage have a high dispersal potential, which probably results in a lower rate of sex reversal.

UBE2I stimulates female gonadal differentiation in chicken(Gallus gallus)embryos

Without known analogous sex-determining factors like SRY(sex determining region Y)in mammals,the chicken(Gallus gallus)sex determination mechanism still remains unclear,which highly restricts the biological research on chicken development and poultry single-sex reproduction.Here we not only characterized a new female-biased gene UBE2I and identified the expression pattern by qRT-PCR,but also described the functional role of UBE2I in the gonadal development of chicken embryos.Results showed that UBE2I exhibited a female-biased expression pattern in the early stage of PGCs(primordial germ cells)in embryonic gonads and robust expression in ovaries of newborn chickens.Most importantly,we successfully developed an effective method to interfere or overexpress UBE2I in chicken embryos through the intravascular injection.The qRT-PCR analysis showed that the sex-related genes(FOXL2,CYP19A1 and HINTW)in females were upregulated(P<0.05)under the overexpression of UBE2I and the sex-related genes(SOX9,DMRT1 and WT1)in females were downregulated(P<0.05)after interfering UBE2I.Furthermore,the change of UBE2I expression was associated with the level of estradiol and its receptors(AR and ESR),which suggests that UBE2I is necessary to initiate the female-specific development in chickens.In conclusion,this work demonstrates that UBE2I is a crucial sex differentiation-related gene in the embryonic development of chickens,which provides insights for further understanding the mechanism of sex determination in chickens.

Identification and Characterization of Gene SpDMRT99B and Its Sex-Biased Expression Profile in the Mud Crab,Scylla paramamosain

The doublesex and mab-3 related transcription factor(DMRT)gene family is conserved from invertebrates to humans.The functions of DMRT are mainly involved in sex development and the formation of many tissues and organs.In this study,a DM(Doublesex/Mab-3-domain gene was identified in the mud crab Scylla paramamosain,and was named SpDMRT99B because of its many similarities to arthropod DMRT99B and phylogenetically close relationship with arthropod DMRT99B.The cDNA of SpDMRT99B gene is 1249 bp in length,encoding 224 amino acids.From 254 bp to 928 bp there is a conserved DM domain.No transmembrane domain was identified.Through multiple amino acid alignment and phylogenetic tree analysis,the closest gene to SpDMRT99B is Eriocheir sinensis DMRT99B,followed by Macrobrachium rosenbergii and Drosophila melanogaster DMRT99B.The expressions of the gene were characterized in different tissues of female and male crabs during early development period of crab individuals,as well as in different development periods of gonads.The results showed that SpDMRT99B gene is significantly highly expressed in testis than in ovary and other tissues.The expression level of SpDMRT99B in testis at different stages is significantly higher than that in ovary,and it is particularly highly expressed in immature testis.In early developmental stages of larvae,the expressions of SpDMRT99B remain at a low level and reach a peak at zoea stage I when the body segments shape up.It is speculated that SpDMRT99B gene might be involved in the gonadal development process and somitogenesis of S.paramamosain.

Early embryonic transcriptomes of Zeugodacus tau provide insight into sex determination and differentiation genes

Zeugodacus tau(Walker)is an invasive pest.The sterile insect technique is an environment-friendly method for pest control.Understanding the mechanism of sex determination will contribute to improving efficiency of this technique.In this study,we identified the transformer(tra)gene in Z.tau.One female-specific and two male-specific isoforms of tra were found in Z.tau,and the male-specific splicing pattern of tra was found to occur 5 h after egg laying.We performed transcriptome sequencing at 1 h(E1),5 h(E5),and 9 h(E9)after egg laying and obtained high-quality transcriptome libraries of early embryo development.We identified 13297 and 11713 differentially expressed genes(DEGs)from E5 versus E1 and E9 versus E1 comparisons,respectively.To explore the potential functions of the DEGs during embryonic development,Gene Ontology,Clusters of Orthologous Groups of proteins,and Kyoto Encyclopedia of Genes and Genomes analyses were performed.Twenty-six genes potentially involved in sex determination or differentiation,including Maleness-on-the-Y(MoY),were identified in Z.tau.To verify the transcriptome results,15 genes were selected for quantitative real-time PCR validation.The results were consistent with the transcriptome sequencing results.Moreover,U2 small nuclear riboprotein auxiliary factor(U2AF-50),female lethal d(fl(2)d),and virilizer(vir)were highly expressed at E5,indicating that they may be related to the sex-specific splicing of tra.Further functional analysis is needed to confirm this speculation.Our data provide an insight into the mechanism underlying sex determination and differentiation in tephritid species.

Pistil Development in 2 Types of Flowers of Xanthoceras sorbifolia

In order to investigate flower development and female abortion during sex differentiation of Xanthoceras sorbifolia, anatomical observations and comparative study on differential proteins were carried out in different developmental stages of two types of flowers of this species. It was found that the selective abortion happened in male flower before the formation of megasporo- cyte. Special proteins related to the female abortion were found through 2-dimensional electrophoretic analysis. Protein A1 (14.2 kD) only existed in florescence of male flower, while B1 (13.7 kD) and B2 (18.2 kD) disappeared in that stage of male flower. They were all considered to be relative to pistil abortion of Xanthoceras sorbifolia.

Effects of Light-Emitting Diode (LED) Red and Blue Light on the Growth and Photosynthetic Characteristics of <i>Momordica charantia</i>L.

With andromonoecious Momordica charantia L. (bitter gourd) as material, three light qualities (50 μmol·m-2·s-1) including white LED light (WL), blue monochromatic light (B, 465 nm), and red monochromatic light (R, 650 nm) were carried out to investigate their effects on seed germination, physiological and biochemical parameters, sex differentiation and photosynthetic characteristics of bitter gourd. The results showed that compared to the WL treatment, the R treatment significantly promoted seed germination, seedling height elongation and soluble sugar content, the B treatment significantly increased seedling stem diameter, reducing sugar content and soluble protein content, the R and B treatments both significantly reduced sucrose content, but their POD activity showed no significant difference. Compared with the R treatment, the B treatment significantly increased the total female flower number and female flower nod ratio in 30 nods of main stems. The study of photosynthetic characteristics found that the R and B treatments could effectively increase the stomatal conductance (GS) of leaves, significantly improved the net photosynthetic rate (Pn) compared to the WL treatment, and the effect of the B treatment was better. Compared to the R and WL treatments, the B treatment increased the maximum photosynthetic rate (Pmax), apparent quantum efficiency (AQE) and light saturation point (LSP), and reduced the dark respiration rate (Rd) and light compensation point (LCP) of the leaves. Fit light response curves showed that the adaptability and utilization of weak light in bitter gourd were middle or below, but it showed higher adaptability and utilization of strong light. Thus, it suggests that Momordica charantia is a typical sun plan with lower Rd. In summary, it is concluded that blue light has a positive effect on the seed germination, seedling growth, sex differentiation and improving the photosynthetic performance, and this will lay the foundation for artificially regulating optimum photosynthesis using specific LEDs wavelength, and help to elucidate the relationship how light quality influences the sex differentiation of plant.

Transcriptional diversity of DMRT1(dsx-and mab3.related transcription factor1)in human testis

Recent advances in the evolutionary genetics of sex determination indicate that the only molecular similarity in sex determination found so far among phyla is between the fly doublesex, worm mab-3 and vertebrate DMRTI（dsx- and mab3-related transcription factor 1）/DMY genes. Each of these factors encodes a zinc-finger-like DNA-binding motif, DM domain. Insights into the evolution and functions of human DMRT1 gene could reveal evolutionary mechanisms of sexual development. Here we report the identification and characterization of multiple isoforms of human DMRT1 in the testis. These transcripts encode predicted proteins with 373,275 and 175 amino acids and they were generated by alternative splicing at 3＇ region. Expression level of DMRTla is higher than those of both DMRTlb and c, and the DMR Tlc expression was the lowest in testis, based on comparisons of mean values from real-time fluorescent quantitative RT-PCR analysis. Both DMRTlb and c result from exonization of intronic sequences, including the exonization of an Alu element. A further search for Alu elements within the DMRT1 gene demonstrated that all 99 Alu elements are non-randomly distributed among the non-coding regions on both directions. These new characteristics of DMRT1 would have an important impact on the evolution of sexual development mechanisms.

Two sex pheromone receptors for sexual communication in the American cockroach

Volatile sex pheromones are vital for sexual communication between males and females.Females of the American cockroach,Periplaneta americana,produce and emit two sex pheromone components,periplanone-A(PA)and periplanone-B(PB).Although PB is the major sex attractant and can attract males,how it interacts with PA in regulating sexual behaviors is still unknown.In this study,we found that in male cockroaches,PA counteracted PB attraction.We identified two odorant receptors(ORs),OR53 and OR100,as PB/PA and PA receptors,respectively.OR53 and OR100 were predominantly expressed in the antennae of sexually mature males,and their expression levels were regulated by the sex differentiation pathway and nutrition-responsive signals.Cellular localization of OR53 and OR100 in male antennae further revealed that two types of sensilla coordinate a complex two-pheromone-two-receptor pathway in regulating cockroach sexual behaviors.These findings indicate distinct functions of the two sex pheromone components,identify their receptors and possible regulatory mechanisms underlying the male-specific and age-dependent sexual behaviors,and can guide novel strategies for pest management.

A CCCH zinc finger gene regulates doublesex alternative splicing and male development in Bombyx mori

Recent identification of a Piwi-interacting RNA(piRNA)-initiated sex determination cascade in the silkworm,Bombyx mori,provides novel insights into high diversity of insect sex determination pathways.In this system,the W-chromosome-derived Fem piRNA is the primary sex determination signal.A CCCH-type zinc finger gene Masculinizer(Masc),which is targeted by Fem piRNA-PIWI complex in female animals,is indispensable for male-specific splicing of B.mori doublesex(Bmdsx).Although many genes involved in this cascade have been identified,the regulatory mechanisms of silk-worm sex determination remain to be elucidated.Here we show that another CCCH-type zinc finger gene,Bmznf-2,is a masculinization factor in B.mori.Bmznf-2 shows testisabundant expression and loss of Bmznf-2 function via clustered regularly interspaced short palindromic repeats 1 single-guide RNA-mediated mutagenesis results in feminized differentiation and appearance of the female-specific splicing variants of Bmdsx transcripts in males.In contrast,there is no phenotypic consequence in mutant females.In mutant males,relative messenger RNA expression levels of female-dominant genes such as vitellogenin and sex-specific storage protein I are significantly clevated while several male-dominant genes are significantly down-regulated.Furthermore,male mutants show delayed developmental timing,smaller body sizes of larvae and malformation of moth wings.Our data thus reveal that Bmznf-2 plays an indispensable role in silkworm male sexual differentiation.

Dynamics of sexual development in teleosts with a note on Mugil cephalus

The process of sex determination(SD)and sex differentiation(Sd)with associated sex-specific behaviour in teleosts is brought about by genetic factors and environmental factors under the influence of chemical messengers.SD is initiated by inherited genes,which in turn influence Sd by the production of hormones.To understand the plasticity of SD in fishes,the functional role of genes must be clearly elucidated.During early development,the dimorphic expression of male and female are mediated by the differentially sexualized brain.In mammals,SD region(SDR)on the Y chromosome(SRY)can be considered as male-specific copy of SOX3 and in the absence of SRY in teleosts suggests SD might be regulated by alternate genes.DM(doublesex/mab)-related genes,AMH(anti-mullerian hormone),TGF-b(transforming growth factor beta),GSDF(gonadal soma derived growth factor)and other genes(around 18)located in chromosomes of teleosts are found to be responsible for SD.The SD gene,sdY(sexually dimorphic on the Y chromosome)has been detected in more than 15 salmonid species,and in medaka and tilapia SD system is governed by heterogametic mechanism.In mullet,Mugil cephalus Dor et al.identified 27 SDR genes and suggested to be potential candidate genes for SD.Recently whole-genome sequencing data were produced from mullet and assembled into a draft genome sequence in which>30 loci are potentially associated with SD.Further analysis is required to know the involvement of each sex-biased gene for its functional influence on sex.Investigators attempted to know the sex-linkage group in tilapia and found that 2 linkage group i.e.LG1 and LG22 show SD loci,whereas in mullet it was documented that LG8 is the SD loci.Rigorous study with all male population(YY)or knockout of male marker gene,might give conclusive understanding on SD in future.The review highlights the absence of genomic understanding of SD and SDR genes for futuristic direction of research.

Sex-biased gene discovery from the gonadal transcriptomes of the large yellow croaker(Larimichthys crocea)

The investigation of sex determination in fish is not only of great scientific value,but also has important practical significance,especially in fishes grown in aquaculture exhibiting obvious growth-related sexual dimorphism,such as the large yellow croaker(Larimichthys crocea).While growth of the female large yellow croaker is faster than that of the male,little information exists on the mechanisms that drive the differentiation of the testis and ovary in this species.In this study,the gene expression profiles of large yellow croaker testis and ovary were analysed using RNA-Seq technology.A total of 222 million reads were mapped to the reference genome(89.80%).The differential gene expression analysis identified 13 genes specifically expressed in ovary and 897 specific to testis.Among these,were candidate sex determining genes,such as Dmrt1,Gsdf,Sox9,Amh.This study explored gene expression profiles in large yellow croaker gonads at the transcriptome level by RNA-Seq technology.We found many DEGs related to the development of each specific organ,including the candidate testis differentiation genes Dmrt1,Gsdf,Sox9,Sox3,Amh and ovary differentiation gene Foxl2 by analogy with other fish species,providing essential foundation clarifying the molecular mechanism involved in early sex differentiation.