Sequence Variations in the Bovine IGF-I and IGFBP3 Genes and Their Association with Growth and Development Traits in Chinese Beef Cattle

The objective of this study was to determine the genotype effects of the bovine insulin-like growth factor Ⅰ （IGF-Ⅰ） and its binding protein 3 （IGFBP3） genes on growth and development traits in beef cows, including 130 Chinese Simmental, 42 Nanyang, and 47 Luxi Yellow cattle. Sequence variations in the bovine IGF-Ⅰ and IGFBP3 genes were investigated by single strand conformation polymorphism （SSCP）. SSCPs were detected in 6 fragments, which is the 5＇-flanking region, the 2nd exon, the 5th exon, and the 5th intron of the IGF-1 gene, and the 2nd exon, the 3rd exon of the 1GFBP3 gene. Two polymorphisms, an A-to-G transition in the 2rid exon of the IGF-Ⅰ gene and a T-to-C transition in the 2rid exon of IGFBP3 gene were detected in 3 breeds. The allele frequencies of 2 polymorphisms were 0.0411 （A）, 0.9589 （B）, and 0.7237 （A）, 0.2763 （B）, respectively. These 2 loci were analyzed to associate with body weight, height at withers, body length, heart girth, rump width, and beef production index （BPI） at 0, 6, 12, 24, and 36-month old. The IGFBP3 locus was shown to be associated with rump width, heart girth at 24-month and 36-month. Animals with BB genotype had higher rump width （24.86 ± 0.47） cm at 24-month and （27.50 ± 0.63） em at 36-month. The heart girth was highest for the individuals with BB genotype （171.33 ± 1.84） cm and higher than those with AB genotype （166.68 ± 1.13） cm （P〈 0.05） at 36-month.

Scientists Identify Different Developmental Trajectories for Individuals with Schizotypal Traits

Schizotypy,defined as the personality organization underlying schizophrenia and other related mental disorders,is a critical construct for a broad range of scientific disciplines.Because schizotypy can be psychometrically identified in the general population,investigating schizotypy may provide a unique

Genetic architecture of quantitative trait loci(QTL)for FHB resistance and agronomic traits in a hard winter wheat population

Wheat resistance to Fusarium head blight(FHB)has often been associated with some undesirable agronomic traits.To study the relationship between wheat FHB resistance and agronomic traits,we constructed a linkage map of single nucleotide polymorphisms(SNPs)using an F6:8 population from G97252WG97380A.The two hard winter wheat parents showed contrasts in FHB resistance,plant height(HT),heading date(HD),spike length(SL),spike compactness(SC),kernel number per spike(KNS),spikelet number per spike(SNS),thousand-grain weight(TGW)and grain size(length and width).Quantitative trait locus(QTL)mapping identified one major QTL(QFhb.hwwg-2DS)on chromosome arm 2DS for the percentage of symptomatic spikelets(PSS)in the spike,deoxynivalenol(DON)content and Fusarium damaged kernel(FDK).This QTL explained up to 71.8%of the phenotypic variation for the three FHB-related traits and overlapped with the major QTL for HT,HD,SL,KNS,SNS,TGW,and grain size.QTL on chromosome arms 2AL,2DS,3AL and 4BS were significant for the spike and grain traits measured.G97252W contributed FHB resistance and high SNS alleles at QFhb.hwwg-2DS,high KNS alleles at the QTL on 2AL and 2DS,and high TGW and grain size alleles at QTL on 3AL;whereas G97380A contributed high TGW and grain size alleles at the QTL on 2AL and 2DS,respectively,and the high KNS allele at the 4BS QTL.Combining QFhb.hwwg-2DS with positive alleles for spike and grain traits from other chromosomes may simultaneously improve FHB resistance and grain yield in new cultivars.

Traits of an invasive grass conferring an early growth advantage over native grasses

Aims Invasive species often have higher relative growth rates(RGR)than their native counterparts.Nutrient use efficiency,total leaf area and specific leaf area(SLA)are traits that may confer RGR differences between natives and invasives,but trait differences are less prominent when the invasive species belongs to the same plant functional type as the dominant native species.Here,we test if traits displayed soon after germination confer an early size advantage.Specifically,we predicted that invasive species seedlings grow faster than the natives because they lack trade-offs that more strongly constrain the growth of native species.Methods We quantified plant morphological and physiological traits and RGR during early seedling growth at high and low nutrient levels in three dominant perennial native C_(4) grasses:Panicum virgatum L.(switchgrass),Schizachyrium scoparium(Michx.)Nash(little bluestem)and Andropogon gerardii Vitman(big bluestem);and a perennial C_(4) exotic invasive grass,Sorghum halepense(L.)Pers.(Johnsongrass).Important Findings After 2 weeks of growth,Johnsongrass seedlings had greater biomass,SLA and photosynthetic nitrogen use efficiency,but lower leaf N concentrations(%leaf N)and root:shoot ratio than natives.As growth continued,Johnsongrass more quickly produced larger and thicker leaves than the natives,which dampened the growth advantage past the first 2 to 3 weeks of growth.Investment in carbon gain appears to be the best explanation for the early growth advantage of Johnsongrass.In natives,growth was constrained by an apparent trade-off between allocation to root biomass,which reduced SLA,and production of leaves with high N content,which increased carbon gain.In Johnsongrass,root:shoot ratio did not interact with other traits,and%leaf N was decoupled from RGR as a result of a trade-off between the positive indirect association of%leaf N with RGR and the negative direct association of%leaf N with RGR.

Gene editing: an instrument for practical application of gene biology to plant breeding

Plant breeding is well recognized as one of the most important means to meet food security challenges caused by the ever-increasing world population. During the past three decades, plant breeding has been empowered by both new knowledge on trait development and regulation(e.g., functional genomics) and new technologies(e.g., biotechnologies and phenomics). Gene editing, particularly by clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas) and its variants, has become a powerful technology in plant research and may become a game-changer in plant breeding. Traits are conferred by coding and non-coding genes. From this perspective, we propose different editing strategies for these two types of genes. The activity of an encoded enzyme and its quantity are regulated at transcriptional and post-transcriptional, as well as translational and post-translational, levels. Different strategies are proposed to intervene to generate gene functional variations and consequently phenotype changes. For non-coding genes, trait modification could be achieved by regulating transcription of their own or target genes via gene editing. Also included is a scheme of protoplast editing to make gene editing more applicable in plant breeding. In summary, this review provides breeders with a host of options to translate gene biology into practical breeding strategies, i.e., to use gene editing as a mechanism to commercialize gene biology in plant breeding.