[PSIP1_HUMAN] Note=A chromosomal aberration involving PSIP1 is associated with pediatric acute myeloid leukemia (AML) with intermediate characteristics between M2-M3 French-American-British (FAB) subtypes. Translocation t(9;11)(p22;p15) with NUP98. The chimeric transcript is an in-frame fusion of NUP98 exon 8 to PSIP1/LEDGF exon 4.
Function
[POL_VILVK] During replicative cycle of retroviruses, the reverse-transcribed viral DNA is integrated into the host chromosome by the viral integrase enzyme. RNase H activity is associated with the reverse transcriptase. [PSIP1_HUMAN] Transcriptional coactivator involved in neuroepithelial stem cell differentiation and neurogenesis. Involved in particular in lens epithelial cell gene regulation and stress responses. May play an important role in lens epithelial to fiber cell terminal differentiation. May play a protective role during stress-induced apoptosis. Isoform 2 is a more general and stronger transcriptional coactivator. Isoform 2 may also act as an adapter to coordinate pre-mRNA splicing. Cellular cofactor for lentiviral integration.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Experimental evidence suggests that a tetramer of integrase (IN) is the protagonist of the concerted strand transfer reaction, whereby both ends of retroviral DNA are inserted into a host cell chromosome. Herein we present two crystal structures containing the N-terminal and the catalytic core domains of maedi-visna virus IN in complex with the IN binding domain of the common lentiviral integration co-factor LEDGF. The structures reveal that the dimer-of-dimers architecture of the IN tetramer is stabilized by swapping N-terminal domains between the inner pair of monomers poised to execute catalytic function. Comparison of four independent IN tetramers in our crystal structures elucidate the basis for the closure of the highly flexible dimer-dimer interface, allowing us to model how a pair of active sites become situated for concerted integration. Using a range of complementary approaches, we demonstrate that the dimer-dimer interface is essential for HIV-1 IN tetramerization, concerted integration in vitro, and virus infectivity. Our structures moreover highlight adaptable changes at the interfaces of individual IN dimers that allow divergent lentiviruses to utilize a highly-conserved, common integration co-factor.
Structural basis for functional tetramerization of lentiviral integrase.,Hare S, Di Nunzio F, Labeja A, Wang J, Engelman A, Cherepanov P PLoS Pathog. 2009 Jul;5(7):e1000515. Epub 2009 Jul 17. PMID:19609359[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑Chylack LT Jr, Fu L, Mancini R, Martin-Rehrmann MD, Saunders AJ, Konopka G, Tian D, Hedley-Whyte ET, Folkerth RD, Goldstein LE. Lens epithelium-derived growth factor (LEDGF/p75) expression in fetal and adult human brain. Exp Eye Res. 2004 Dec;79(6):941-8. PMID:15642333 doi:S0014-4835(04)00250-7
↑Hare S, Di Nunzio F, Labeja A, Wang J, Engelman A, Cherepanov P. Structural basis for functional tetramerization of lentiviral integrase. PLoS Pathog. 2009 Jul;5(7):e1000515. Epub 2009 Jul 17. PMID:19609359 doi:10.1371/journal.ppat.1000515
