Homologous Superfamily

RNA polymerase, phosphoprotein P, C-terminal XD, paramyxovirinae (IPR016075)

Short name: RNA_pol_Pprot-P_XD_paramyxovir

Overlapping entries


Paramyxovirinae has a negative-sense ssRNA genome that is packaged by the viral nucleoprotein (N) within a helical nucleocapsid. The N-RNA (nucleoprotein-RNA) complex is used as a template for both transcription and replication. During viral genome replication, the synthesis of viral RNA and its encapsidation by N are concomitant. Viral transcription and replication are carried out by viral RNA-dependent RNA polymerase, which consists of two proteins: L polymerase and phosphoprotein P. The L polymerase carries the enzyme activity. Phosphoprotein P binds the viral nucleocapsid, and positions the L polymerase on the template for transcription and replication formed by nucleoprotein-RNA (N-RNA).

Phosphoprotein P, an indispensable subunit of the viral polymerase complex, is a modular protein organised into two moieties that are both functionally and structurally distinct: a well-conserved C-terminal moiety that contains all the regions required for transcription, and a poorly conserved, intrinsically unstructured N-terminal moiety that provides several additional functions required for replication. The N-terminal moiety is responsible for binding to newly synthesized free N(0) (nucleoprotein that has not yet bound RNA), in order to prevent the binding of N(0) to cellular RNA. The C-terminal moiety consists of an oligomerisation domain, an N-RNA (nucleoprotein-RNA)-binding domain and an L polymerase-binding domain.

This entry represents the XD domain found at the extreme C-terminal of the C-terminal moiety of phosphoprotein P from several Paramyxovirinae, including Measles virus [PMID: 12944395, PMID: 15159535], Canine distemper virus and Sendai virus [PMID: 14980481, PMID: 17459940, PMID: 10400742].

GO terms

Biological Process

GO:0006351 transcription, DNA-templated
GO:0019079 viral genome replication

Molecular Function

GO:0003723 RNA binding
GO:0003968 RNA-directed 5'-3' RNA polymerase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.