Huang Jinling, Mullapudi Nandita, Sicheritz-Ponten Thomas, Kissinger Jessica C
Center for Tropical and Emerging Global Diseases, University of Georgia, 623 Biological Sciences, Athens, GA 30602-2606, USA.
Int J Parasitol. 2004 Mar 9;34(3):265-74. doi: 10.1016/j.ijpara.2003.11.025.
Reports of plant-like and bacterial-like genes for a number of parasitic organisms, most notably those within the Apicomplexa and Kinetoplastida, have appeared in the literature over the last few years. Among the apicomplexan organisms, following discovery of the apicomplexan plastid (apicoplast), the discovery of plant-like genes was less surprising although the extent of transfer and the relationship of transferred genes to the apicoplast remained unclear. We used new genome sequence data to begin a systematic examination of the extent and origin of transferred genes in the Apicomplexa combined with a phylogenomic approach to detect potential gene transfers in four apicomplexan genomes. We have detected genes of algal nuclear, chloroplast (cyanobacterial) and proteobacterial origin. Plant-like genes were detected in species not currently harbouring a plastid (e.g. Cryptosporidium parvum) and putatively transferred genes were detected that appear to be unrelated to the function of the apicoplast. While the mechanism of acquisition for many of the identified genes is not certain, it appears that some were most likely acquired via intracellular gene transfer from an algal endosymbiont while others may have been acquired via horizontal gene transfer.
在过去几年的文献中，出现了许多寄生生物具有植物样和细菌样基因的报道，最显著的是顶复门和动质体门中的生物。在顶复门生物中，随着顶复门质体（apicoplast）的发现，植物样基因的发现就不那么令人惊讶了，尽管基因转移的程度以及转移基因与顶复门质体的关系仍不清楚。我们利用新的基因组序列数据，开始系统研究顶复门中转移基因的程度和起源，并结合系统发育基因组学方法来检测四个顶复门基因组中的潜在基因转移。我们检测到了来自藻类细胞核、叶绿体（蓝细菌）和变形菌的基因。在目前没有质体的物种（如微小隐孢子虫）中检测到了植物样基因，并且检测到了一些推测的转移基因，这些基因似乎与顶复门质体的功能无关。虽然许多已鉴定基因的获取机制尚不确定，但似乎有些基因很可能是通过细胞内基因转移从藻类内共生体获得的，而其他一些基因可能是通过水平基因转移获得的。
