Recurrent Amplification of the Heterochromatin Protein 1 (HP1) Gene Family across Diptera.
Recurrent Amplification of the Heterochromatin Protein 1 (HP1) Gene Family across Diptera.
复制标题
DOI：
10.1093/molbev/msy128
复制
发表时间：
2018-10-01
影响因子：
10.7
通讯作者：
Levine MT
中科院分区：
文献类型：
--
作者：
Helleu Q;Levine MT
异染色质基因组区室介导严格保守的细胞过程，如染色体分离，端粒完整性和基因组稳定性。特别是异染色质DNA序列是非常不保守的。最近的报道，许多杂交不相容基因编码异染色质蛋白，以及观察到种间杂交遭受异常异染色质依赖的过程，表明异染色质DNA包装需要物种特异性的创新。测试这种快速进化的异染色质DNA及其包装蛋白之间的共同进化模型，首先要定义后者。在这里，我们描述了许多这样的候选人编码的异染色质蛋白1（HP 1）基因家族双翅目，昆虫订单，包括戏剧性的插曲异染色质序列营业额。通过BLAST、同线性分析和系统发育树构建，我们在64个双翅目基因组中发现了惊人的121个HP 1重复事件。相比之下，我们观察到几乎没有基因重复的基因家族，共享一个共同的“染色体结构域”与HP 1，包括Polycomb和苏（var）3-9。双翅目HP 1旁系同源物的显着高的数量来自遥远的分支进行收敛HP 1家庭扩增。这些独立衍生的年轻HP 1跨越了不同的年龄、结构域结构和分子进化速率，包括正选择事件。此外，独立衍生的HP 1表现出趋同的表达进化。虽然古老的HP 1亲本基因被普遍转录，但年轻的HP 1旁系同源物主要在雄性生殖系组织中转录，这是年轻基因的典型模式。普遍存在的基因年轻，快速进化和生殖系专业化牵连异染色质编码自私的元素驱动经常性HP 1基因家族的扩张。这121个年轻的基因为阐明由双翅目异染色质周转的许多戏剧性事件所形成的种系过程提供了有价值的实验牵引力。
The heterochromatic genome compartment mediates strictly conserved cellular processes such as chromosome segregation, telomere integrity, and genome stability. Paradoxically, heterochromatic DNA sequence is wildly unconserved. Recent reports that many hybrid incompatibility genes encode heterochromatin proteins, together with the observation that interspecies hybrids suffer aberrant heterochromatin-dependent processes, suggest that heterochromatic DNA packaging requires species-specific innovations. Testing this model of coevolution between fast-evolving heterochromatic DNA and its packaging proteins begins with defining the latter. Here we describe many such candidates encoded by the Heterochromatin Protein 1 (HP1) gene family across Diptera, an insect Order that encompasses dramatic episodes of heterochromatic sequence turnover. Using BLAST, synteny analysis, and phylogenetic tree building across 64 Diptera genomes, we discovered a staggering 121 HP1 duplication events. In contrast, we observed virtually no gene duplication in gene families that share a common “chromodomain” with HP1s, including Polycomb and Su(var)3-9. The remarkably high number of Dipteran HP1 paralogs arises from distant clades undergoing convergent HP1 family amplifications. These independently derived, young HP1s span diverse ages, domain structures, and rates of molecular evolution, including episodes of positive selection. Moreover, independently derived HP1s exhibit convergent expression evolution. While ancient HP1 parent genes are transcribed ubiquitously, young HP1 paralogs are transcribed primarily in male germline tissue, a pattern typical of young genes. Pervasive gene youth, rapid evolution, and germline specialization implicate heterochromatin-encoded selfish elements driving recurrent HP1 gene family expansions. The 121 young genes offer valuable experimental traction for elucidating the germline processes shaped by Diptera’s many dramatic episodes of heterochromatin turnover.
登录
查看更多内容
影响因子：
7.7
作者：
Drinnenberg IA;deYoung D;Henikoff S;Malik HS
通讯作者：
Malik HS
截止值抑制 RNA 聚合酶 II 终止，以确保 piRNA 前体的表达。
影响因子：
16
作者：
Chen YA;Stuwe E;Luo Y;Ninova M;Le Thomas A;Rozhavskaya E;Li S;Vempati S;Laver JD;Patel DJ;Smibert CA;Lipshitz HD;Toth KF;Aravin AA
通讯作者：
Aravin AA
影响因子：
3.7
作者：
Freitas LA;Russo CA;Voloch CM;Mutaquiha OC;Marques LP;Schrago CG
通讯作者：
Schrago CG
影响因子：
10.7
作者：
Dion-Cote, Anne-Marie;Renaut, Sebastien;Bernatchez, Louis
通讯作者：
Bernatchez, Louis
影响因子：
3.3
作者：
Gallach, Miguel
通讯作者：
Gallach, Miguel