5FSW

RNA dependent RNA polymerase QDE-1 from Thielavia terrestris

5FSW の概要

• エントリーDOI: 10.2210/pdb5fsw/pdb
• 分子名称: RNA DEPENDENT RNA POLYMERASE QDE-1 (1 entity in total)
• 機能のキーワード: transferase, small rnas, qde-1 orthologues, evolution
• 由来する生物種: THIELAVIA TERRESTRIS
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 464235.44

構造登録者

Qian, X.,Hamid, F.M.,El Sahili, A.,Darwis, D.A.,Wong, Y.H.,Bhushan, S.,Makeyev, E.V.,Lescar, J. (登録日: 2016-01-08, 公開日: 2016-03-02, 最終更新日: 2024-01-10)

主引用文献

Qian, X.,Hamid, F.M.,El Sahili, A.,Darwis, D.A.,Wong, Y.H.,Bhushan, S.,Makeyev, E.V.,Lescar, J.
Functional Evolution in Orthologous Cell-Encoded RNA-Dependent RNA Polymerases
J.Biol.Chem., 291:9295-, 2016

PubMed Abstract: Many eukaryotic organisms encode more than one RNA-dependent RNA polymerase (RdRP) that probably emerged as a result of gene duplication. Such RdRP paralogs often participate in distinct RNA silencing pathways and show characteristic repertoires of enzymatic activities in vitro However, to what extent members of individual paralogous groups can undergo functional changes during speciation remains an open question. We show that orthologs of QDE-1, an RdRP component of the quelling pathway in Neurospora crassa, have rapidly diverged in evolution at the amino acid sequence level. Analyses of purified QDE-1 polymerases from N. crassa (QDE-1(Ncr)) and related fungi, Thielavia terrestris (QDE-1(Tte)) and Myceliophthora thermophila (QDE-1(Mth)), show that all three enzymes can synthesize RNA, but the precise modes of their action differ considerably. Unlike their QDE-1(Ncr) counterpart favoring processive RNA synthesis, QDE-1(Tte) and QDE-1(Mth) produce predominantly short RNA copies via primer-independent initiation. Surprisingly, a 3.19 Å resolution crystal structure of QDE-1(Tte) reveals a quasisymmetric dimer similar to QDE-1(Ncr) Further electron microscopy analyses confirm that QDE-1(Tte) occurs as a dimer in solution and retains this status upon interaction with a template. We conclude that divergence of orthologous RdRPs can result in functional innovation while retaining overall protein fold and quaternary structure.

PubMed: 26907693
DOI: 10.1074/JBC.M115.685933

実験手法

X-RAY DIFFRACTION (3.19 Å)