title: Cloning and characterization of the human homolog of mouse Jak2.
abstract: Members of the Jak family play a critical role in signal transduction mediated by cytokine and hormone receptors. In this study, we report the cloning and characterization of human Jak2. The predicted amino acid sequence shows 91% homology to the described murine Jak2, but with a significant difference in the extreme C-terminal sequence. Using the human cDNA as a probe, we localized the gene for human Jak2 to chromosome 9p23-24. Human Jak2 mRNA is highly expressed in the spleen, lymph nodes, and peripheral blood lymphocytes (PBLs). A polyclonal antibody raised against the unique C-terminus of human Jak2 was used to characterize Jak2 protein. Levels of Jak2 protein expression increased significantly in mitogen- and anti-IgM-stimulated B cells and to a lesser degree in activated T cells. In addition, high levels of Jak2 protein were detected in pre-B leukemia cells.
authors.affiliation: Department of Pediatrics, University of Toronto, Ontario, Canada.
authors.forename: I
authors.initials: I
authors.lastname: Dalal
authors.forename: E
authors.initials: E
authors.lastname: Arpaia
authors.forename: H
authors.initials: H
authors.lastname: Dadi
authors.forename: S
authors.initials: S
authors.lastname: Kulkarni
authors.forename: J
authors.initials: J
authors.lastname: Squire
authors.forename: C M
authors.initials: CM
authors.lastname: Roifman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D003001:Cloning, Molecular; D015342:DNA Probes; D015870:Gene Expression; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D053614:Janus Kinase 2; D008221:Lymphoid Tissue / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D011505:Protein-Tyrosine Kinases / Q000737:chemistry / Q000235:genetics*; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger / Q000032:analysis; D017385:Sequence Homology; D015398:Signal Transduction; D014018:Tissue Distribution
chemical_list: D015342:DNA Probes; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; C507926:Jak2 protein, mouse; D053614:Janus Kinase 2