6LBK

Structure of rat GLD-2 (Terminal nucleotidyltransferase 2, TENT2)

Summary for 6LBK

• Entry DOI: 10.2210/pdb6lbk/pdb
• Descriptor: Poly(A) RNA polymerase GLD2 (2 entities in total)
• Functional Keywords: mrna processing, 5'-3' rna polymerase activity, dna polymerase type-b-like family, terminal nucleotidyltransferase 2, transferase
• Biological source: Rattus norvegicus (Rat)
• Total number of polymer chains: 2
• Total formula weight: 87641.27

Authors

Ma, X.Y.,Gao, S. (deposition date: 2019-11-14, release date: 2020-07-22, Last modification date: 2023-11-22)

Primary citation

Ma, X.Y.,Zhang, H.,Feng, J.X.,Hu, J.L.,Yu, B.,Luo, L.,Cao, Y.L.,Liao, S.,Wang, J.,Gao, S.
Structures of mammalian GLD-2 proteins reveal molecular basis of their functional diversity in mRNA and microRNA processing.
Nucleic Acids Res., 48:8782-8795, 2020

PubMed Abstract: The stability and processing of cellular RNA transcripts are efficiently controlled via non-templated addition of single or multiple nucleotides, which is catalyzed by various nucleotidyltransferases including poly(A) polymerases (PAPs). Germline development defective 2 (GLD-2) is among the first reported cytoplasmic non-canonical PAPs that promotes the translation of germline-specific mRNAs by extending their short poly(A) tails in metazoan, such as Caenorhabditis elegans and Xenopus. On the other hand, the function of mammalian GLD-2 seems more diverse, which includes monoadenylation of certain microRNAs. To understand the structural basis that underlies the difference between mammalian and non-mammalian GLD-2 proteins, we determine crystal structures of two rodent GLD-2s. Different from C. elegans GLD-2, mammalian GLD-2 is an intrinsically robust PAP with an extensively positively charged surface. Rodent and C. elegans GLD-2s have a topological difference in the β-sheet region of the central domain. Whereas C. elegans GLD-2 prefers adenosine-rich RNA substrates, mammalian GLD-2 can work on RNA oligos with various sequences. Coincident with its activity on microRNAs, mammalian GLD-2 structurally resembles the mRNA and miRNA processor terminal uridylyltransferase 7 (TUT7). Our study reveals how GLD-2 structurally evolves to a more versatile nucleotidyltransferase, and provides important clues in understanding its biological function in mammals.

PubMed: 32633758
DOI: 10.1093/nar/gkaa578

Experimental method

X-RAY DIFFRACTION (2.4956881144 Å)