Differential age-dependent import regulation by signal peptides.
Differential age-dependent import regulation by signal peptides.
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DOI：
10.1371/journal.pbio.1001416
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发表时间：
2012
期刊：
影响因子：
9.8
通讯作者：
Li HM
中科院分区：
文献类型：
--
作者：
Teng YS;Chan PT;Li HM
某些蛋白质进入叶绿体依赖于细胞器的年龄，年龄依赖性输入由信号肽内的特定基序控制。基因特异性的、年龄依赖性的调节在转录和翻译水平上是常见的，而蛋白质转运到细胞器中通常被认为是组成性的。在这里，我们报告了一个新的水平的差异的年龄依赖性调节，并表明，叶绿体蛋白质分为三个年龄选择性组：I组蛋白质有更高的进口效率到年轻的叶绿体，进口的II组蛋白质几乎是独立的叶绿体年龄，和III组蛋白质优先进口到老年人的叶绿体。年龄选择性信号位于每个蛋白质的转运肽内。第III组蛋白的转运肽被第I组转运肽取代，未能补充其自身的突变。两个连续的正电荷定义了必要的基序在第III组信号的老叶绿体的偏好。我们进一步表明，一个基因家族的不同成员往往属于不同的年龄选择性组，因为它们的转运肽序列的差异。这些结果表明，细胞器靶向信号肽是细胞的差异年龄依赖性调节网络的一部分。一些细胞器靶向肽的序列多样性不是缺乏选择压力的结果，而是已经进化为介导调节。众所周知，一些基因在年轻组织中优先转录，而另一些基因在衰老组织中特异性表达，但蛋白质进入细胞器通常被认为是组成性的，与年龄无关。在这项研究中，我们发现，与预期相反，在高等植物中，蛋白质进入叶绿体的输入确实依赖于细胞器的年龄。我们发现，叶绿体前体蛋白可以分为三个年龄选择性组，每个有一个不同年龄的叶绿体的偏好。年龄选择性信号位于控制细胞器进口的每个蛋白质的信号肽内，我们进一步确定了一个基序，这是必要的，使信号肽优先靶向较老的叶绿体。我们发现，一个基因家族的不同成员往往属于不同的年龄选择性群体，改变蛋白质的信号肽内的序列基序可以改变其年龄选择性。这些结果表明，细胞器靶向信号肽是一套工具，可用于多细胞生物的差异年龄特异性调节。
The import of certain proteins into chloroplasts is dependent on the age of the organelle, with age-dependent import being controlled by a specific motif within the signal peptide. Gene-specific, age-dependent regulations are common at the transcriptional and translational levels, while protein transport into organelles is generally thought to be constitutive. Here we report a new level of differential age-dependent regulation and show that chloroplast proteins are divided into three age-selective groups: group I proteins have a higher import efficiency into younger chloroplasts, import of group II proteins is nearly independent of chloroplast age, and group III proteins are preferentially imported into older chloroplasts. The age-selective signal is located within the transit peptide of each protein. A group III protein with its transit peptide replaced by a group I transit peptide failed to complement its own mutation. Two consecutive positive charges define the necessary motif in group III signals for older chloroplast preference. We further show that different members of a gene family often belong to different age-selective groups because of sequence differences in their transit peptides. These results indicate that organelle-targeting signal peptides are part of cells' differential age-dependent regulation networks. The sequence diversity of some organelle-targeting peptides is not a result of the lack of selection pressure but has evolved to mediate regulation. It is well known that some genes are preferentially transcribed in young tissues and others are specifically expressed in aging tissue, but protein import into organelles is generally thought to be constitutive and independent of age. In this study, we find that, contrary to expectation, in higher plants the import of proteins into chloroplasts is indeed dependent on the age of the organelle. We find that chloroplast precursor proteins can be divided into three age-selective groups, with each having a preference for chloroplasts of a different age. The age-selective signal is located within the signal peptide of each protein that controls organelle import, and we further identify a motif that is necessary to make a signal peptide target older chloroplasts preferentially. We show that different members of a gene family often belong to different age-selective groups, and that changing the sequence motifs within a protein's signal peptide can change its age selectivity. These results indicate that organelle-targeting signal peptides are one set of tools available to multicellular organisms for differential age-specific regulation.
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影响因子：
1.6
作者：
Aatsinki, JT;Rajaniemi, HJ
通讯作者：
Rajaniemi, HJ
影响因子：
11.6
作者：
Kubis, S;Patel, R;Jarvis, P
通讯作者：
Jarvis, P
影响因子：
11.6
作者：
Li, HM;Chen, LJ
通讯作者：
Chen, LJ
影响因子：
11.6
作者：
Lee, Sookjin;Lee, Dong Wook;Hwang, Inhwan
通讯作者：
Hwang, Inhwan
DOI：
10.1083/jcb.200804157
发表时间：
2008-07-28
期刊：
The Journal of cell biology
影响因子：
--
作者：
Hegde RS;Kang SW
通讯作者：
Kang SW