Anti-DDX4/MVH Antibody Picoband® (monoclonal, 3C3) Fluoro647 Conjugated

DDX4 (DEAD/H BOX 4), also known as VASA. The deduced 724-amino acid VASA protein contains the 8 conserved domains found in all known DEAD box proteins. The amino acid sequence in this core region shows greater similarity to VASA homologs in other species than to other human DEAD box proteins. By radiation hybrid analysis, Castrillon et al. (2000) mapped the VASA gene to 5q. By fluorescence in situ hybridization, they refined the localization to 5q11.2-q12. This region is syntenic to the distal end of mouse chromosome 13, where the mouse VASA homolog (Ddx4) resides (Abe and Noce, 1997) . Using a combination of proteomics, cytology, and functional analysis in C. elegans, Chu et al. (2006) reduced 1,099 proteins copurified with spermatogenic chromatin to 132 proteins for functional analysis.

PPIases accelerate the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. Proposed to act as a co-chaperone in HSP90 complexes such as in unligated steroid receptors heterocomplexes. Different co-chaperones seem to compete for association with HSP90 thus establishing distinct HSP90-co-chaperone-receptor complexes with the potential to exert tissue-specific receptor activity control. May have a preference for estrogen receptor complexes and is not found in glucocorticoid receptor complexes. May be involved in cytoplasmic dynein-dependent movement of the receptor from the cytoplasm to the nucleus. May regulate MYB by inhibiting its DNA- binding activity. Involved in regulation of AHR signaling by promoting the formation of the AHR:ARNT dimer; the function is independent of HSP90 but requires the chaperone activity. Involved in regulation of UV radiation-induced apoptosis. Promotes cell viability in anaplastic lymphoma kinase-positive anaplastic large- cell lymphoma (ALK+ ALCL) cell lines. May be involved in hepatitis C virus (HCV) replication and release.

1. Abe, K., Noce, T. A DEAD-family protein gene, Ddx4, encoding a murine homolog of Drosophila vasa maps to the distal end of mouse chromosome 13. Mammalian Genome 8: 622-623, 1997. 2. Castrillon, D. H., Quade, B. J., Wang, T. Y., Quigley, C., Crum, C. P. The human VASA gene is specifically expressed in the germ cell lineage. Proc. Nat. Acad. Sci. 97: 9585-9590, 2000. 3. Chu, D. S., Liu, H., Nix, P., Wu, T. F., Ralston, E. J., Yates, J. R., III, Meyer, B. J. Sperm chromatin proteomics identifies evolutionarily conserved fertility factors. Nature 443: 101-105, 2006.