地山雀(Parushumilis)是青藏高原的特有鳥種,屬山雀科鳥類。由於其形態特徵與地鴉相近,曾長期被認為是鴉科鳥類,並被命名為「褐背擬地鴉」。
中科院動物研究所動物進化與系統學院重點實驗室雷富民研究員領導的鳥類學研究組與諾禾致源合作,對地山雀開展全基因組denovo測序,同時對另外兩種山雀(大山雀和黃頰山雀)以及黑尾地鴉進行了重測序比較分析。研究結果從基因組水平進一步確證了地山雀是「山雀」而非「鴉」的分類地位,並初步揭示了該物種適應青藏高原極端環境的遺傳印跡。
結果顯示,地山雀與黃頰山雀、大山雀的親緣關係很近,估算分化時間在7.7-9.9個百萬年之間。通過與原雞、火雞和斑胸草雀的基因組數據比較,發現地山雀基因組中與能量代謝相關的基因家族發生了擴張,而與免疫和嗅覺相關的基因家族發生了收縮;通過對7190個直系同源基因的比對,發現與低氧反應和骨骼發育相關的基因經歷了正向選擇以及不同程度的快速進化。上述結果進一步揭示了地山雀為適應青藏高原的特殊環境,產生了基本的生存適應策略演化,以及由山雀向鴉的形態特徵轉變。
該成果於7月1日在線發表於Nature Communications雜誌上。(生物谷 Bioon.com)
生物谷推薦的英文摘要
Nature Communications doi:10.1038/ncomms3071
Ground tit genome reveals avian adaptation to living at high altitudes in the Tibetan plateau
Yanhua Qu, Hongwei Zhao, Naijian Han, Guangyu Zhou, Gang Song, Bin Gao, Shilin Tian, Jinbo Zhang, Ruiying Zhang, Xuehong Meng, Yuan Zhang, Yong Zhang, Xiaojia Zhu, Wenjuan Wang, David Lambert, Per G. P. Ericson, Sankar Subramanian, Carol Yeung, Hongmei Zhu, Zhi Jiang, Ruiqiang Li & Fumin Lei
The ground tit (Parus humilis) is endemic to the Tibetan plateau. It is a member of family Paridae but it was long thought to be related to the ground jays because of their morphological similarities. Here we present the ground tit’s genome and re-sequence two tits and one ground jay, to clarify this controversially taxonomic status and uncover its genetic adaptations to the Tibetan plateau. Our results show that ground tit groups with two tits and it diverges from them between 7.7 and 9.9 Mya. Compared with other avian genomes, ground tit shows expansion in genes linked to energy metabolism and contractions in genes involved in immune and olfactory perception. We also found positively selected and rapidly evolving genes in hypoxia response and skeletal development. These results indicated that ground tit evolves basic strategies and 『tit-to-jay』 change for coping with the life in an extreme environment.