Molecular characterization of two candidate genes associated with coat color in Tibetan sheep(Ovis arise)

Coat color is a key economic trait in sheep. Some candidate genes associated with animal＇s coat color were found. Partic- ularly, v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog （KIT） and microphthalmia-associated transcription factor （MITF） play a key role in the modulation of hair pigmentation in mammals. This study investigated those two candidate genes＇ mutations and expressions associated with wool color in Tibetan sheep. First, the gene polymorphisms of those two genes were analyzed, and then, relative mRNA expression levels of those two genes in skin tissue with different coat colors were compared. Thirdly, KIT and MITF protein expression levels were detected through Western blot and immune- histochemical. Allele C was predominant allele in the white coat color Tibetan sheep population of the MITF coding region g. 1548 C/T loci. The relative MITF mRNA expression in black coat skin tissue was significantly higher than white （P〈0.01）. However, no significant differences were detected in the KIT gene＇s mRNA expression of these two different coat color skin tissues （P〉0.05）, while the level of KIT protein expression in skin tissues of white and black coats was also roughly equivalent. Our study observed that, the level of MITF protein expression in black coat skin tissue was significantly higher than that in white coat skin tissue, and positive staining for MITF protein expression was detected mainly in the epidermis and the dermal papilla, bulb, and outer root sheath of hair follicles. We conclude that the black coat of Tibetan sheep is related to high MITF expression in the hair follicles, and MITF may be important for coat color formation of Tibetan sheep.

Study on Red Coat Color Gene and Prediction of the Secondary Structure in Chinese Holstein

The nucleotide sequence of the melanocortin-l-receptor （MC1R） gene was studied with the help of the polymerase chain reaction （PCR）, in which the protein structure in Chinese Holstein was predicted, and the molecular mechanism of the red coat color was investigated. Polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） was performed to genotype the individuals. The bioinformatics and biotechnology softwares were used to predict the secondary structure of MC1R. The results showed that the EE genotype was the dominant genotype in Chinese Holstein Black and White herd, whereas, it was ee in Chinese Holstein Red and White herd. The secondary structure of the mutational MC1R protein was changed and the deletion mutation caused an earlier termination in translation, which led to the formation of the red coat color. The allele E was mainly associated with the black coat color, whereas, e was associated with red.

Comparison of Five Selection Procedures for Seed Coat and Hilum Color in Interspecific Crossing of Soybeans

Five selection procedures for seed coat and hilum color were studied with F4 progenies in two interspecific crossing of soybeans. The seed coat and hilum color indicated that pedigree, 5% and 10% mass selection method were equally successful, and were better than picking-pod and 25% mass selection in cross S17. However, no significant differences in seed coat and hilum color were found in cross G18.

Corrosion resistance properties of colored zirconium conversion coating and powder coating on cold-rolled steel

Jiuhe Corporation developed a new surface pretreatment for producing a phosphate-free and colored zirconium conversion coating on cold-rolled steel(CRS).Scanning electron microscopy(SEM)and energy-dispersive spectroscopy(EDS)were applied to study the surface morphology and elemental composition of the golden yellow-colored conversion coating.Elec trochemic al impedance spectroscopy(EIS)was used to investigate the electrochemical performance of the conversion coatings with different colors.The corrosion resistance properties of the powder coatings were characterized using the neutral salt spray test(NSS)and the tape adhesion test.The EIS and NSS results demonstrate that the colored zirconium conversion coatings exhibit excellent corrosion resistance properties compared with the bare CRS.The golden yellow-colored conversion coating has a maximum EIS value(748Ω·cm^(2))and achieves 0 mm degree of corrosion,as stipulated by EN ISO 4628-8.This paper proposes a hypothesis concerning the ZrO_(2)-(β-FeOOH)-polymer conversion reaction to explain the color changes.

Fine-mapping and primary analysis of candidate genes associated with seed coat color in mung bean(Vigna radiata L.)

Seed coat color affects the appearance and commodity quality of mung beans(Vigna radiata L.).The substances that affect mung bean seed coat color are mainly flavonoids,which have important medicinal value.Mapping the seed coat color gene in mung beans would facilitate the development of new varieties and improve their value.In this study,an F2 mapping population consisting of 546 plants was constructed using Jilv9(black seed coat)and BIS9805(green seed coat).Using bulk segregated analysis(BSA)sequencing and kompetitive allele-specific PCR(KASP)markers,the candidate region related to seed coat color was finally narrowed to 0.66 Mb on chromosome(Chr.)4 and included eight candidate genes.Combined transcriptome and metabolome analyses showed that three of the eight candidate genes(LOC106758748,LOC106758747,and LOC106759075)were differentially expressed,which may have caused the differences in flavonoid metabolite content between Jilv9 and BIS9805.These findings can provide a research basis for cloning the genes related to seed coat color and accelerate molecular markerassisted selection breeding in mung beans.

Characteristics of Genetic Resources of Kazakh Horse

In order to understand the characteristics of genetic resources of Kazakh horses in Xinjiang,their body size,phenotypes and coat colors were investigated and analyzed using the methods of resources survey and body size measurement. The results showed that the coat color of Kazakh horses in Xinjiang is very rich,covering more than 90% of the world＇s horse coat colors. The influencing factors of Kazakh horse body size data might include the environment and geographical distribution of Kazakh horses. The gap between Xinjiang Kazakh horse and Kazakhstan Kazakh horse was relatively large,which was related to the degree of breeding.There were some differences in the appearance of Kazakh horses between Altay and Ili regions with different ecological environment. The Kazakh horses in Altay were relatively strong in size,well developed in coat and long hair,long and dense in fuzz in winter,and rich in coat color. But the Kazakh horses in Ili were compact in size,less in coat than those in Altay,and have a single coat color.

Genetic structure and domestication footprints of the tusk,coat color,and ear morphology in East Chinese pigs

The domestication and artificial selection of wild boars have led to dramatic morphological and behavioral changes,especially in East Chinese(ECN)pigs.Here,we provide insights into the population structure and current genetic diversity of representative ECN pig breeds.We identify a 500-kb region containing six tooth development-relevant genes with almost completely different haplotypes between ECN pigs and Chinese wild boars or European domestic pigs.Notably,the c.195A>G missense mutation in exon 2 of AMBN may cause alterations in its protein structure associated with tusk degradation in ECN pigs.In addition,ESR1 may play an important role in the reproductive performance of ECN pigs.A major haplotype of the large lop ear-related MSRB3 gene and eight alleles in the deafness-related GRM7 gene may affect ear morphology and hearing in ECN pigs.Interestingly,we find that the two-end black(TEB)coat color in Jinhua pigs is most likely caused by EDNRB with genetic mechanisms different from other Chinese TEB pigs.This study identifies key loci that may be artificially selected in Chinese native pigs related to the tusk,coat color,and ear morphology,thus providing new insights into the genetic mechanisms of domesticated pigs.

A chromosome-level genome assembly of chia provides insights into high omega-3 content and coat color variation of its seeds

Chia(Salvia hispanica)is a functional food crop for humans.Although its seeds contain high omega-3 fatty acids,the seed yield of chia is still low.Genomic resources available for this plant are limited.We report the first high-quality chromosome-level genome sequence of chia.The assembled genome size was 347.6 Mb and covered 98.1%of the estimated genome size.A total of 31069 protein-coding genes were predicted.The absence of recent whole-genome duplication and the relatively low intensity of transposable element expansion in chia compared to its sister species contribute to its small genome size.Transcriptome sequencing and gene duplication analysis reveal that the expansion of the fab2 gene family is likely to be related to the high content of omega-3 in seeds.The white seed coat color is determined by a single locus on chromosome 4.This study provides novel insights into the evolution of Salvia species and high omega-3 content,as well as valuable genomic resources for genetic improvement of important commercial traits of chia and its related species.

Genomic regions under selection for important traits in domestic horse breeds

Horses were domesticated 5500 years ago,thousands of years later than other domestic animals;however, in this relatively short period, domestic horses have had a great impact on human history by accelerating civilization, revolutionizing warfare and advancing agricultural production. Modern breeding using markerassisted selection has greatly accelerated breeding progress. Therefore, identification of genetic markers underlying the traits of interest in domestic horses is the basis for the modern breeding system. In this review, we present an overview of genetic mapping studies and genome wide analyses to identify the genomic regions targeted by positive selection for four important aspects of horses, coat color, racing performance, gait and height at withers. The MC1 R locus, for example, has been shown to be the main gene responsible for chestnut color, and the MSTN locus has been shown to control the muscle fiber growth in racing breeds. The missense mutation in DMRT3 is the causal mutation for the alternate gaits in horses. Height at withers, a quantitative trait, was mapped to four major loci(3:105547002, 6:81481064, 9:75550059 and 11:23259732) that can explain 83% of the height variations in domestic horses.