MLK-3: identification of a widely-expressed protein kinase bearing an SH3 domain and a leucine zipper-basic region domain.
We have identified a novel protein kinase, designated MLK-3, from human thymus using RT-PCR and cDNA library screening. The deduced open reading frame, derived from sequencing a 3.5 kb MLK-3 cDNA, encodes a protein of 847 amino acids with several interesting structural features. These include an SH3 domain in the absence of an SH2 domain, a region containing two leucine zippers with an adjacent carboxy-terminal basic region, and a proline rich region. This kinase shows homology with the mixed-lineage family of protein kinases (MLK) and shares the unusual leucine zipper-basic motif found in previously identified MLK kinases. By northern analysis, MLK-3 mRNA was detected in a wide variety of normal and transformed human cell lines and tissue specimens. The gene encoding MLK-3 has been mapped using fluorescence in situ hybridization to human chromosome 11 q13.1-13.3, a region frequently altered in human malignancies.
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Department of Clinical Biochemistry, University of Toronto, Ontario.
Leung
I W
IW
Heng
H H
HH
Tsui
L C
LC
Lassam
N J
NJ
D000595:Amino Acid Sequence; D001483:Base Sequence; D002460:Cell Line; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11; D006801:Humans; D016350:Leucine Zippers; D008969:Molecular Sequence Data; D011494:Protein Kinases / Q000737:chemistry* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis
D012333:RNA, Messenger; D011494:Protein Kinases