title: Type II PtdIns 4-kinase β associates with CD4-p56lck complex and is involved in CD4 receptor signaling.
abstract: Type II phosphatidylinositol (PtdIns) 4-kinases are involved in the synthesis of PtdIns 4-phosphates and modulate various cell functions like, intracellular signaling, cytoskeletal rearrangements, vesicular trafficking, and pathogen invasion. In CD3 receptor activated T cells, a type II PtdIns 4-kinase β is recruited to CD3 receptor zeta and plays a role in intracellular calcium release and probably in actin cytoskeleton reorganization. T cell receptor mediated activation is supported by CD4 receptor. The role of type II PtdIns 4-kinase β in CD4 receptor-mediated signaling was addressed in the present manuscript. Crosslinking of CD4 receptors with monoclonal antibodies showed an increase in CD4-associated PtdIns 4-kinase activity and requires p56(lck) activity. Biochemical characterization suggests that it belongs to type II PtdIns 4-kinase family. shRNA mediated knockdown of type II PtdIns 4-kinase β showed abrogation of CD4 receptor induced intracellular calcium release. These results suggest that type II PtdIns 4-kinase β plays an integral part in CD4 receptor-mediated signaling.
authors: Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, 400076, India, ranjeet@scripps.edu.
authors: Ranjeet Kumar
authors: RK
authors: Sinha
authors: Naveen
authors: N
authors: Bojjireddy
authors: Deepak
authors: D
authors: Kanojia
authors: Gosukonda
authors: G
authors: Subrahmanyam
mesh_terms: D015704:CD4 Antigens / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D006801:Humans; D019169:Jurkat Cells; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000378:metabolism*; D015778:Minor Histocompatibility Antigens; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D015704:CD4 Antigens; D015778:Minor Histocompatibility Antigens; D017853:Phosphotransferases (Alcohol Group Acceptor); C402182:phosphatidylinositol phosphate 4-kinase; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D002118:Calcium