摘要
Multiprotein bridging factor 1 （MBF1） is a transcriptional co-activator related to stress tolerance in various organisms. We investigated the nucleotide differences in the mbfl gene in the lichen-forming fungus Umbilicaria decussata collected from polar （i.e., Antarctica and the Arctic） and non-polar （i.e., Armenia） regions. The 552-bp Udmbfl genes isolated from eight samples contained numerous sequence variations, including single nucleotide polymorphisms as well as insertions and deletions. The frequency of nucleotide changes was higher in the intron than in the coding sequence. The nucleotide polymorphism levels （n=0.01792, 0=-0.01792） and haplotype diversity （Hd=-l） in the Udmbfl gene from Antarctic samples were relatively high. Additionally, of the 19 detected nucleotide sequence variation sites, 15 were observed only in Antarctic samples. The resulting amino acid changes occurred in the N-terminal, whose function remains unknown. Although these DNA polymorphisms and amino acid changes have been verified in Antarctic samples of U. decussata, there is still little evidence indicating that different environmental conditions affected the functional evolution of Udmbfl. Additional studies involving more U. decussata samples fi＇om representative ecotypes will be necessary to tmcover the relationships among DNA polymorphisms, functional gene evolution, and lichen habitats.
Multiprotein bridging factor 1 （MBF1） is a transcriptional co-activator related to stress tolerance in various organisms. We investigated the nucleotide differences in the mbfl gene in the lichen-forming fungus Umbilicaria decussata collected from polar （i.e., Antarctica and the Arctic） and non-polar （i.e., Armenia） regions. The 552-bp Udmbfl genes isolated from eight samples contained numerous sequence variations, including single nucleotide polymorphisms as well as insertions and deletions. The frequency of nucleotide changes was higher in the intron than in the coding sequence. The nucleotide polymorphism levels （n=0.01792, 0=-0.01792） and haplotype diversity （Hd=-l） in the Udmbfl gene from Antarctic samples were relatively high. Additionally, of the 19 detected nucleotide sequence variation sites, 15 were observed only in Antarctic samples. The resulting amino acid changes occurred in the N-terminal, whose function remains unknown. Although these DNA polymorphisms and amino acid changes have been verified in Antarctic samples of U. decussata, there is still little evidence indicating that different environmental conditions affected the functional evolution of Udmbfl. Additional studies involving more U. decussata samples fi＇om representative ecotypes will be necessary to tmcover the relationships among DNA polymorphisms, functional gene evolution, and lichen habitats.
基金
supported by grants from the National Natural Science Foundation of China (Grant no.31500012)
the Chinese Arctic and Antarctic Administration (Grant no.2016YR05005)
