Anti-HAX1 Antibody Picoband® Fluoro594 Conjugated

HCLS1-associated protein X-1 is a protein that in humans is encoded by the HAX1 gene. The protein encoded by this gene is known to associate with hematopoietic cell-specific Lyn substrate 1, a substrate of Src family tyrosine kinases. It also interacts with the product of the polycystic kidney disease 2 gene, mutations in which are associated with autosomal-dominant polycystic kidney disease, and with the F-actin-binding protein, cortactin. It was earlier thought that this gene product is mainly localized in the mitochondria, however, recent studies indicate it to be localized in the cell body. Mutations in this gene result in autosomal recessive severe congenital neutropenia, also known as Kostmann disease. Two transcript variants encoding different isoforms have been found for this gene.

Cyclin-dependent kinase 8; Cell division protein kinase 8; Mediator complex subunit CDK8; Mediator of RNA polymerase II transcription subunit CDK8; Protein kinase K35; CDK8

Predominantly expressed in the liver (PubMed:11099417, PubMed:11452359) . Low expression levels in the small intestine and colon (PubMed:11099417) . Very low levels in other tissues, including brain, heart and spleen (PubMed:11452359) .

Component of the Mediator complex, a coactivator involved in regulated gene transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. Mediator is recruited to promoters by interactions with regulatory proteins and serves as a scaffold for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. Phosphorylates the CTD (C-terminal domain) of the large subunit of RNA polymerase II (RNAp II), which may inhibit the formation of a transcription initiation complex. Phosphorylates CCNH leading to down-regulation of the TFIIH complex and transcriptional repression. Recruited through interaction with MAML1 to hyperphosphorylate the intracellular domain of NOTCH, leading to its degradation.

1. Carlsson, G., Fasth, A. Infantile genetic agranulocytosis, morbus Kostmann: presentation of six cases from the original 'Kostmann family' and a review. Acta Paediat. 90: 757-764, 2001. 2. Chao, J.-R., Parganas, E., Boyd, K., Hong, C. Y., Opferman, J. T., Ihle, J. N. Hax1-mediated processing of HtrA2 by Parl allows survival of lymphocytes and neurons. Nature 452: 98-102, 2008. Note: Erratum: Nature 452: 900 only, 2008. 3. Dale, D. C., Person, R. E., Bolyard, A. A., Aprikyan, A. G., Bos, C., Bonilla, M. A., Boxer, L. A., Kannourakis, G., Zeidler, C., Welte, K., Benson, K. F., Horwitz, M. Mutations in the gene encoding neutrophil elastase in congenital and cyclic neutropenia. Blood 96: 2317-2322, 2000.