4fw2
From Proteopedia
Crystal structure of RSV three-domain integrase with disordered N-terminal domain
Structural highlights
FunctionPOL_RSVP Capsid protein p27 forms the spherical core of the virus that encapsulates the genomic RNA-nucleocapsid complex (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell (By similarity). Publication Abstract from PubMedIntegration of the retrovirus linear DNA genome into the host chromosome is an essential step in the viral replication cycle, and is catalyzed by the viral integrase (IN). Evidence suggests that IN functions as a dimer that cleaves a dinucleotide from the 3' DNA blunt ends while a dimer of dimers (tetramer) promotes concerted integration of the two processed ends into opposite strands of a target DNA. However, it remains unclear why a dimer rather than a monomer of IN is required for the insertion of each recessed DNA end. To help address this question, we have analyzed crystal structures of the Rous sarcoma virus (RSV) IN mutants complete with all three structural domains as well as its two-domain fragment in a new crystal form at an improved resolution. Combined with earlier structural studies, our results suggest that the RSV IN dimer consists of highly flexible N-terminal domains and a rigid entity formed by the catalytic and C-terminal domains stabilized by the well-conserved catalytic domain dimerization interaction. Biochemical and mutational analyses confirm earlier observations that the catalytic and the C-terminal domains of an RSV IN dimer efficiently integrates one viral DNA end into target DNA. We also show that the asymmetric dimeric interaction between the two C-terminal domains is important for viral DNA binding and subsequent catalysis, including concerted integration. We propose that the asymmetric C-terminal domain dimer serves as a viral DNA binding surface for RSV IN. A possible role for the asymmetric C-terminal domain dimer of Rous sarcoma virus integrase in viral DNA binding.,Shi K, Pandey KK, Bera S, Vora AC, Grandgenett DP, Aihara H PLoS One. 2013;8(2):e56892. doi: 10.1371/journal.pone.0056892. Epub 2013 Feb 22. PMID:23451105[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||
