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The genus Macaca serves as an ideal research model for speciation and introgressive gene flow due to its short period of diversification (about five million years ago) and rapid radiation of constituent species. To understand evolutionary gene flow in macaques, we sequenced four whole genomes (two M. arctoides and two M. thibetana) and combined them with publicly available macaque genome data for genome-wide analyses. We analyzed 14 individuals from nine Macaca species covering all Asian macaque species groups and detected extensive gene flow signals, with the strongest signals between the fascicularis and silenus species groups. Notably, we detected bidirectional gene flow between M. fascicularis and M. nemestrina. The estimated proportion of the genome inherited via gene flow between the two species was 6.19%. However, the introgression signals found among studied island species, such as Sulawesi macaques and M. fuscata, and other species were largely attributed to the genomic similarity of closely related species or ancestral introgression. Furthermore, gene flow signals varied in individuals of the same species (M. arctoides, M. fascicularis, M. mulatta, M. nemestrina and M. thibetana), suggesting very recent gene flow after the populations split. Pairwise sequentially Markovian coalescence (PSMC) analysis showed all macaques experienced a bottleneck five million years ago, after which different species exhibited different fluctuations in demographic history trajectories, implying they have experienced complicated environmental variation and climate change. These results should help improve our understanding of the complicated evolutionary history of macaques, particularly introgressive gene flow.

Pikas (Lagomorpha: Ochotonidae) are small mouse-like lagomorphs. To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang (Tibet) Plateau (QTP), we collected 226 pikas and measured 20 morphological characteristics and recorded habitat information. We also sequenced the genome of 81 specimens, representing 27 putative pika species. The genome-wide tree based on 4 090 coding genes identified five subgenera, i.e.,鼠兔（兔形目:鼠兔科）是一种小型的哺乳动物。为了研究鼠兔从青藏高原迁徙过程中对不同生态环境的适应性进化，我们采集了226只鼠兔并测量了每个个体的20项形态特征数据，还记录了它们的生境信息。我们进一步对代表了27个推定的不同鼠兔物种的81个标本进行了基因组测序。基于4090个编码基因的全基因组系统发育树和形态学数据，我们均鉴定出5个鼠兔亚属，即

During the breast-feeding period, infants undergo remarkable changes, including rapid physiological and developmental growth. However, little is known about gene expression features and sex-specific gene expression in breast-feeding infants. In this study, we sequenced 32 blood transcriptomes from 16 breast-feeding rhesus macaque (Macaca mulatta) infants and their lactating mothers. We identified 218 differentially expressed genes (DEGs) between infants and mothers, including 91 up-regulated and 127 down-regulated DEGs in the infant group. Functional enrichment analysis of the up-regulated DEGs and unique hub genes in infants showed primary enrichment in immunity, growth, and development. Protein-protein interaction analysis also revealed that genes at key positions in infants were mainly related to development and immunity. However, we only detected 23 DEGs between female and male infants, including three DEGs located on chromosome X and 14 DEGs located on chromosome Y. Of these DEGs, TMF1 regulated nuclear protein 1 (Trnp1), which was highly expressed in female infants, is crucial for controlling the tangential and radial expansion of the cerebral cortex in mammals. Thus, our study provides novel insight into the gene expression features of breast-feeding infants in non-human primates (NHPs) and reveals sex-specific gene expression between these infants.

Changes in gene expression occur as animals, including primates, age. Macaques have long been used as a model species for primate evolution and biomedical studies. Here, to study gene expression in Tibetan macaques (Macaca thibetana, TMs) and its differences to humans, we applied RNA-Seq to obtain the blood transcriptomes of 24 TMs. In total, 2 523 age-associated differentially expressed genes (DEGs) were identified. Several pathways and processes that regulate aging, including the FoxO signaling pathway, autophagy, and platelet activation, were significantly enriched in the up-regulated DEGs. Two significantly age-related modules were identified by weighted gene co-expression network analysis (WGCNA). The TMs and humans shared 279 common DEGs, including 111 up-regulated and 141 down-regulated genes with advancing age in the same expression direction. However, 27 age-related DEGs presented the opposite expression direction in TMs as that in humans. For example, INPPL1, with inhibitory effects on the B cell receptor signaling pathway, was up-regulated in humans but down-regulated in TMs. In general, our study suggests that aging is a critical factor affecting gene expression in the captive TM population. The similarities and differences in gene expression patterns between TMs and humans could provide new insights into primate evolution and benefit TM model development.

The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature (IUCN)(2017). Short tandem repeats (STRs) refer to repetitive elements of genome sequence that range in length from 1–6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software (lobSTR), we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals (P