Integrative genomics reveals paths to sex dimorphism in Salix purpurea L

Sex dimorphism and gene expression were studied in developing catkins in 159 F 2 individuals from the bioenergy crop Salix purpurea,and potential mechanisms and pathways for regulating sex development were explored.Differential expression,eQTL,bisulfite sequencing,and network analysis were used to characterize sex dimorphism,detect candidate master regulator genes,and identify pathways through which the sex determination region(SDR)may mediate sex dimorphism.Eleven genes are presented as candidates for master regulators of sex,supported by gene expression and network analyses.These include genes putatively involved in hormone signaling,epigenetic modification,and regulation of transcription.eQTL analysis revealed a suite of transcription factors and genes involved in secondary metabolism and floral development that were predicted to be under direct control of the sex determination region.Furthermore,data from bisulfite sequencing and small RNA sequencing revealed strong differences in expression between males and females that would implicate both of these processes in sex dimorphism pathways.These data indicate that the mechanism of sex determination in Salix purpurea is likely different from that observed in the related genus Populus.This further demonstrates the dynamic nature of SDRs in plants,which involves a multitude of mechanisms of sex determination and a high rate of turnover.

Trilineage Sequencing Reveals Complex TCRβTranscriptomes in Neutrophils and Monocytes Alongside T Cells

Recent findings indicate the presence of T cell receptor(TCR)-based combinatorial immune receptors beyond T cells in neutrophils and monocytes/macrophages.In this study,using a semiquantitative trilineage immune repertoire sequencing approach as well as under rigorous bioinformatic conditions,we identify highly complex TCRβtranscriptomes in human circulating monocytes and neutrophils that separately encode repertoire diversities one and two orders of magnitude smaller than that of T cells.Intraindividual transcriptomic analyses reveal that neutrophils,monocytes,and T cells express distinct TCRβrepertoires with less than 0.1%overall trilineage repertoire sharing.Interindividual comparison shows that in all three leukocyte lineages,the vast majority of the expressed TCRβvariants are private.We also find that differentiation of monocytes into macrophages induces dramatic individual-specific repertoire shifts,revealing a surprising degree of immune repertoire plasticity in the monocyte lineage.These results uncover the remarkable complexity of the two phagocyte-based flexible immune systems which until now has been hidden in the shadow of T cells.

Whole-genome sequences shed light on the demographic history and contemporary genetic erosion of free-ranging jaguar(Panthera onca) populations

Whole-genome sequences provide massive amounts of data that can illuminate many aspects of a species’biology and evolutionary history,as well as valuable information for conservation planning.This is particularly important for large carnivores,whose large area requirements and typical low densities make them prone to undergo rapid genetic erosion(e.g.accumulation of runs of homozygosity,Diez del Molino et al.,2018;Leroy et al.,2018)in the face of habitat loss and human persecution.One such species is the jaguar(Pan-thera onca),the largest extant felid in the Americas,whose range has already declined by>50%and some of whose remaining popu-lations have been severely impacted by human-induced habitat frag-mentation(De La Torre et al.,2018).