Dataset Information

Elevational divergence in the great tit complex revealed by major hemoglobin genes.

ABSTRACT: Gene flow and demographic history can play important roles in the adaptive genetic differentiation of species, which is rarely understood in the high-altitude adaptive evolution of birds. To elucidate genetic divergence of populations in the great tit complex (Parus major, P. minor and P. cinereus) at different elevations, we compared the genetic structure and gene flow in hemoglobin genes with neutral loci. Our results revealed the elevationally divergent structure of ? A -globin gene, distinctive from that of the ? A -globin gene and neutral loci. We further investigated gene flow patterns among the populations in the central-northern (>?1,000 m a.s.l.), south-eastern (?2,000 m a.s.l.) in China. The high-altitude (>?1,000 m a.s.l.) diverged ? A -globin genetic structure coincided with higher ? A -globin gene flow between highland populations, in contrast to restricted neutral gene flow concordant with the phylogeny. The higher ? A -globin gene flow suggests the possibility of adaptive evolution during population divergence, contrary to the lower ? A -globin gene flow homogenized by neutral loci during population expansion. In concordance with patterns of historical gene flow, genotypic and allelic profiles provide distinctive patterns of fixation in different high-altitude populations. The fixation of alleles at contrasting elevations may primarily due to highland standing variants ? A 49Asn/72Asn/108Ala originating from the south-western population. Our findings demonstrate a pattern of genetic divergence with gene flow in major hemoglobin genes depending on population demographic history.

SUBMITTER: ZHu X

PROVIDER: S-EPMC6084574 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Elevational divergence in the great tit complex revealed by major hemoglobin genes.

ZHu Xiaojia X Guan Yuyan Y Qu Yanhua Y David Gabriel G Song Gang G Lei Fumin F

Current zoology 20170706 4

Gene flow and demographic history can play important roles in the adaptive genetic differentiation of species, which is rarely understood in the high-altitude adaptive evolution of birds. To elucidate genetic divergence of populations in the great tit complex (Parus major, P. minor and P. cinereus) at different elevations, we compared the genetic structure and gene flow in hemoglobin genes with neutral loci. Our results revealed the elevationally divergent structure of α <su ...[more]

PMID: 30108626

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Project description:The uropygial gland (preen gland) of birds plays an important role in maintaining feather integrity and hygiene. Although a few studies have demonstrated potential defensive roles of bacteria residing within these glands, the diversity and functions of the uropygial gland microbiota are largely unknown. Therefore, we investigated the microbiota of great tit (Parus major) uropygial glands through both isolation of bacteria (culture-dependent) and 16S rRNA amplicon sequencing (culture-independent). Co-culture experiments of selected bacterial isolates with four known feather-degrading bacteria (Bacillus licheniformis, Kocuria rhizophila, Pseudomonas monteilii, and Dermacoccus nishinomiyaensis), two non-feather degrading feather bacteria, one common soil bacterial pathogen and two common fungal pathogens enabled us to evaluate the potential antimicrobial properties of these isolates. Our results show major differences between bacterial communities characterized using culture-dependent and -independent approaches. In the former, we were only able to isolate 12 bacterial genera (dominated by members of the Firmicutes and Actinobacteria), while amplicon sequencing identified 110 bacterial genera (dominated by Firmicutes, Bacteroidetes, and Proteobacteria). Uropygial gland bacterial isolates belonging to the genera Bacillus and Kocuria were able to suppress the growth of four of the nine tested antagonists, attesting to potential defensive roles. However, these bacterial genera were infrequent in our MiSeq results suggesting that the isolated bacteria may not be obligate gland symbionts. Furthermore, bacterial functional predictions using 16S rRNA sequences also revealed the ability of uropygial gland bacteria to produce secondary metabolites with antimicrobial properties, such as terpenes. Our findings support that uropygial gland bacteria may play a role in feather health and that bacterial symbionts might act as defensive microbes. Future investigations of these bacterial communities, with targeted approaches (e.g., bacterial isolation and chemical analyses), are thus warranted to improve our understanding of the evolution and function of these host-microbe interactions.

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Dataset Information

Elevational divergence in the great tit complex revealed by major hemoglobin genes.

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Elevational divergence in the great tit complex revealed by major hemoglobin genes.

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