Diplonemid glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and prokaryote-to-eukaryote and lateral gene transfer
Diplonemid glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and prokaryote-to-eukaryote and lateral gene transfer
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DOI：
10.1078/1434-4610-00059
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发表时间：
2001-09-01
期刊：
影响因子：
2.5
通讯作者：
Keeling, PJ
中科院分区：
文献类型：
--
作者：
Qian, Q;Keeling, PJ
横向基因转移是指遗传信息从一个基因组转移到另一个基因组，并将外源DNA整合到新的遗传环境中。目前只有少数得到充分支持的情况下，原核细胞到真核细胞转移已知的不涉及线粒体或质体，但不清楚这是否反映了缺乏这样的转移事件，或不同的真核生物的采样差。其中该过程明显活跃的一个基因是甘油醛-3-磷酸脱氢酶（GAPDH），其中横向转移已涉及裸藻样和动质体基因的起源。我们的特点是GAPDH基因的diplonemids，异养鞭毛虫，动质体和裸藻密切相关。在dipleonemid中发现了两种不同的dipleonemid GAPDH基因，然而，这两种基因都与任何其他裸藻动物GAPDH没有密切关系。一个diplonemid GAPDH与真核生物的胞质gapC有关，但与裸藻或动质体无关，第二个与蓝藻和变形菌gap 3有关。细菌gap 3基因在diplonemids提供了一个最好的支持的例子，从细菌到真核生物的横向基因转移的特点，到目前为止，并可能表明，diplonemids已获得一种新的生化能力，通过横向转移。
Lateral gene transfer refers to the movement of genetic information from one genome to another, and the integration of that foreign DNA into its new genetic environment. There are currently only a few well-supported cases of prokaryote-to-eukaryote transfer known that do not involve mitochondria or plastids, but it is not clear whether this reflects a lack of such transfer events, or poor sampling of diverse eukaryotes. One gene where this process is apparently active is glyceraldehyde-3-phosphate dehydrogenase (GAPDH), where lateral transfer has been implicated in the origin of euglenoid and kinetoplastid genes. We have characterised GAPDH genes from diplonemids, heterotrophic flagellates that are closely related to kinetoplastids and euglenoids. Two distinct classes of diplonemid GAPDH genes were found in diplonemids, however, neither class is closely related to any other euglenozoan GAPDH. One diplonemid GAPDH is related to the cytosolic gapC of eukaryotes, although not to either euglenoids or kinetoplastids, and the second is related to cyanobacterial and proteobacterial gap3. The bacterial gap3 gene in diplonemids provides one of the most well-supported examples of lateral gene transfer from a bacterium to a eukaryote characterised to date, and may indicate that diplonemids have acquired a novel biochemical capacity through lateral transfer.