Anti-ANP32A (full length) polyclonal antibody

pp32 (ANP32A) is a nuclear phosphoprotein expressed as a nomnutated form in self-renewing cell populations and neoplastic cells. Mechanistically, PP32 may regulate pathways important in the process of differentiation as part of separate complexes inhibiting histone acetylation and regulating immediate-early and cytokine mRNA stability. Prostatic adenocarcinomas express pp32 in a differentiation related manner-well-differentiated tumors express lower levels of PP32 than poorly differentiated tumors. In benign prostate, PP32 is expressed in basal cells but not in terminally differentiated glandular cells. Based on these observations, we hypothesized that reduction of pp32 expression might be an important differentiation signal. We used antisense pp32 and RNAi transfection to study the effects of reduced pp32 expression in the TSU-Pr1 carcinoma cell line. pp32 reduction induced Tsu-Pr1 cells to differentiate into neuronal-like cells with associated inhibition of growth. Reduction of pp32 and consequent differentiation were accompanied by a marked reduction in expression of SET, which complexes with PP32, by a marked change in acetylation status of histone 114, and by further differential expression of genes in differentiation pathways. Thus, reduction of PP32 in the undifferentiated TSU-Pr1 neoplastic cell line induces differentiation and thus may be an element of a differentiation control pathway in both normal and neoplastic cells.

Host restriction of influenza A virus limits pandemic emergence. The viral RNA polymerase (vPol) is an essential enzyme that must adapt for avian viruses to replicate in humans. Species differences in host ANP32A dictate adaptation: human ANP32A lacks an uncharacterized 33 amino-acid insertion that is present in avian ANP32A. Here, we uncover important contributions of host SUMOylation to vPol activity, including avANP32A function. We also identify a hydrophobic SUMO interaction motif (SIM)-like sequence unique to avANP32A that critically supports avian-signature vPol. Unrelated SIM sequences partially recapitulate this function when introduced into huANP32A. By investigating ANP32A-vPol interactions, we find that huANP32A interacts weakly with both human-and avian-signature vPols, while the hydrophobic motif of avANP32A promotes stronger interactions. Furthermore, we identify a highly acidic stretch in avANP32A that constitutes a major site of vPol interaction. Our data suggest compensatory mechanisms underlying vPol adaptation to host ANP32A independent of species-specific interactions.