3U1K

Crystal structure of human PNPase

3U1K の概要

• エントリーDOI: 10.2210/pdb3u1k/pdb
• 分子名称: Polyribonucleotide nucleotidyltransferase 1, mitochondrial, CITRIC ACID (3 entities in total)
• 機能のキーワード: rnase ph, kh domain, exoribonuclease, transferase
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Cytoplasm: Q8TCS8
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 276775.43

構造登録者

Lin, C.L.,Yuan, H.S. (登録日: 2011-09-30, 公開日: 2012-02-01, 最終更新日: 2023-11-01)

主引用文献

Lin, C.L.,Wang, Y.-T.,Yang, W.-Z.,Hsiao, Y.-Y.,Yuan, H.S.
Crystal structure of human polynucleotide phosphorylase: insights into its domain function in RNA binding and degradation
Nucleic Acids Res., 40:4146-4157, 2012

PubMed Abstract: Human polynucleotide phosphorylase (hPNPase) is a 3'-to-5' exoribonuclease that degrades specific mRNA and miRNA, and imports RNA into mitochondria, and thus regulates diverse physiological processes, including cellular senescence and homeostasis. However, the RNA-processing mechanism by hPNPase, particularly how RNA is bound via its various domains, remains obscure. Here, we report the crystal structure of an S1 domain-truncated hPNPase at a resolution of 2.1 Å. The trimeric hPNPase has a hexameric ring-like structure formed by six RNase PH domains, capped with a trimeric KH pore. Our biochemical and mutagenesis studies suggest that the S1 domain is not critical for RNA binding, and conversely, that the conserved GXXG motif in the KH domain directly participates in RNA binding in hPNPase. Our studies thus provide structural and functional insights into hPNPase, which uses a KH pore to trap a long RNA 3' tail that is further delivered into an RNase PH channel for the degradation process. Structural RNA with short 3' tails are, on the other hand, transported but not digested by hPNPase.

PubMed: 22210891
DOI: 10.1093/nar/gkr1281

実験手法

X-RAY DIFFRACTION (2.13 Å)