对两个品种蚂蚁的基因组的比较给了科学家们一些线索:究竟是什么决定了一只蚂蚁的命运是成为工蚁还是蚁后。 不同等级的蚂蚁有着相同的基因蓝图,但它们会因为影响其基因表达的“表观遗传学”的变化而发育成为完全不同的个体。 在佛罗里达弓背蚁( Camponotus floridanus)的群体中,只有蚁后才会产下受精卵;当该蚁后死亡时,该蚂蚁的群体也随之死亡。 该蚁群中的其它蚂蚁或是主要工蚁或是次要工蚁,它们有着不同的生理学和行为学差异。 相反,在印度跳蚁(Harpegnathos saltator) 的群体中,蚁后与工蚁的身体差别没有那么明显,而且在蚁后死亡时,某个工蚁会进而成为蚁后。 Roberto Bonasio以及一个国际性同事的团队现在对这两种蚂蚁的基因组进行了测序。 他们对基因表达进行了比较并发现了可能与诸如RNA介导的信号转导和甲基化等基因调节的表观变化有关的差异。 本文的作者说,这一研究除了对造成这两种蚂蚁的不同等级间存在分子差异的原因提供了线索之外,它还建立了一个研究衰老和行为的表观遗传学的新的实验模型。
原文出处:
Science DOI: 10.1126/science.1192428
Genomic Comparison of the Ants Camponotus floridanus and Harpegnathos saltator
Roberto Bonasio,1,* Guojie Zhang,2,3,* Chaoyang Ye,4,* Navdeep S. Mutti,5,* Xiaodong Fang,3,* Nan Qin,3,* Greg Donahue,4 Pengcheng Yang,3 Qiye Li,3 Cai Li,3 Pei Zhang,3 Zhiyong Huang,3 Shelley L. Berger,4, Danny Reinberg,1,6, Jun Wang,3,7, Jürgen Liebig5,
The organized societies of ants include short-lived worker castes displaying specialized behavior and morphology and long-lived queens dedicated to reproduction. We sequenced and compared the genomes of two socially divergent ant species: Camponotus floridanus and Harpegnathos saltator. Both genomes contained high amounts of CpG, despite the presence of DNA methylation, which in non-Hymenoptera correlates with CpG depletion. Comparison of gene expression in different castes identified up-regulation of telomerase and sirtuin deacetylases in longer-lived H. saltator reproductives, caste-specific expression of microRNAs and SMYD histone methyltransferases, and differential regulation of genes implicated in neuronal function and chemical communication. Our findings provide clues on the molecular differences between castes in these two ants and establish a new experimental model to study epigenetics in aging and behavior.
1 Department of Biochemistry, New York University School of Medicine, 522 First Avenue, New York, NY 10016, USA.
2 Chinese Academy of Sciences–Max Planck Junior Research Group, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
3 Beijing Genomics Institute–Shenzhen, Shenzhen 518083, China.
4 Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
5 School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA.
6 Howard Hughes Medical Institute, New York University Medical School, New York, NY 10016, USA.
7 Department of Biology, University of Copenhagen, Copenhagen DK-2200, Denmark.