Arabidopsis Contains Ancient Classes of Differentially Expressed Actin-Related Protein Genes1
Arabidopsis Contains Ancient Classes of Differentially Expressed Actin-Related Protein Genes1
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DOI：
10.1104/pp.010906
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发表时间：
2002-03
期刊：
影响因子：
7.4
通讯作者：
E. C. McKinney;M. Kandasamy;R. Meagher
中科院分区：
文献类型：
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作者：
E. C. McKinney;M. Kandasamy;R. Meagher
肌动蛋白相关蛋白（ARPs）与常规肌动蛋白的氨基酸序列同源性不到60%，并在细胞质和细胞核的多种细胞骨架过程中发挥作用。对拟南芥进行了ARP基因家族成员的基因组探索。8个潜在的ARP基因序列分散在拟南芥5条染色体中的3条染色体上。AtARP2和AtARP3是其他王国中名称相似的蛋白同源物。AtARP4、AtARP5和AtARP6是先前在动物和真菌中发现的两类核ARPs BAF53s和ARP6s的同源物。AtARP7和AtARP8似乎是与任何已知的动物或真菌ARPs没有密切关系的新蛋白，可能是植物特异性的。复杂的拟南芥ARP基因结构每个包含5到20个外显子。通过AtARP8鉴定和表征了AtARP2的表达转录物，但没有发现AtARP9的表达转录物，并且发现了AtARP8的两个剪接变体的转录物。预计这7个表达的基因编码的蛋白质长度从146到471个氨基酸不等。与传统的肌动蛋白和其他ARPs相比，AtARP2和AtARP3转录本在所有器官中的表达水平都很低。AtARP5、AtARP6和AtARP8在幼苗、根、叶、花和叶鞘中都有不同的转录表达模式。利用等变异体特异性单克隆抗体，AtARP4和AtARP7蛋白在花中表达量最高。简要讨论了植物ARPs可能参与肌动蛋白成核、肌动蛋白丝分支、染色质重组和转录。
Actin-related proteins (ARPs) share less than 60% amino acid sequence homology with conventional actins and have roles in diverse cytoskeletal processes in the cytoplasm and nucleus. The genome of Arabidopsis was explored for possible ARP gene family members. Eight potential ARP gene sequences were found dispersed on three of the five Arabidopsis chromosomes. AtARP2 and AtARP3 are protein orthologs of their similarly named counterparts in other kingdoms. AtARP4, AtARP5, and AtARP6 are orthologs of two classes of nuclear ARPs previously characterized in animals and fungi, BAF53s and ARP6s. AtARP7 and AtARP8 appear to be novel proteins that are not closely related to any known animal or fungal ARPs, and may be plant specific. The complex Arabidopsis ARP gene structures each contain from five to 20 exons. Expressed transcripts were identified and characterized for AtARP2 through AtARP8, but not for AtARP9, and transcripts representing two splice variants were found for AtARP8. The seven expressed genes are predicted to encode proteins ranging from 146 to 471 amino acids in length. Relative to conventional actin and the other ARPs, AtARP2 and AtARP3 transcripts are expressed at very low levels in all organs. AtARP5,AtARP6, and AtARP8 each have distinct transcript expression patterns in seedlings, roots, leaves, flowers, and siliques. Using isovariant-specific monoclonal antibodies, AtARP4 and AtARP7 proteins were shown to be most highly expressed in flowers. The likely involvement of plant ARPs in actin nucleation, branching of actin filaments, chromatin restructuring, and transcription are briefly discussed.