Interaction of 5-lipoxygenase with cellular proteins.
5-Lipoxygenase (5LO) plays a pivotal role in cellular leukotriene synthesis. To identify proteins interacting with human 5LO, we used a two-hybrid approach to screen a human lung cDNA library. From a total of 1.5 x 10(7) yeast transformants, nine independent clones representing three different proteins were isolated and found to specifically interact with 5LO. Four 1.7- to 1.8-kb clones represented a 16-kDa protein named coactosin-like protein for its significant homology with coactosin, a protein found to be associated with actin in Dictyostelium discoideum. Coactosin-like protein thus may provide a link between 5LO and the cytoskeleton. Two other yeast clones of 1.5 kb encoded transforming growth factor (TGF) type beta receptor-I-associated protein 1 partial cDNA. TGF type beta receptor-I-associated protein 1 recently has been reported to associate with the activated form of the TGF beta receptor I and may be involved in the TGF beta-induced up-regulation of 5LO expression and activity observed in HL-60 and Mono Mac 6 cells. Finally, three identical 2.1-kb clones contained the partial cDNA of a human protein with high homology to a hypothetical helicase K12H4. 8 from Caenorhabditis elegans and consequently was named DeltaK12H4. 8 homologue. Analysis of the predicted amino acid sequence revealed the presence of a RNase III motif and a double-stranded RNA binding domain, indicative of a protein of nuclear origin. The identification of these 5LO-interacting proteins provides additional approaches to studies of the cellular functions of 5LO.
Provost
P
P
Department of Medical Biochemistry and Biophysics, Division of Chemistry II, Karolinska Institute, S-171 77 Stockholm, Sweden.
Samuelsson
B
B
Rådmark
O
O
D030201:Activin Receptors, Type I; D000595:Amino Acid Sequence; D000818:Animals; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism*; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000201:enzymology; D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular; D004023:Dictyostelium / Q000378:metabolism; D004722:Endoribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism; D015723:Gene Library; D017930:Genes, Reporter; D018922:HL-60 Cells; D006801:Humans; D008168:Lung / Q000201:enzymology; D008840:Microfilament Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D015800:Protozoan Proteins / Q000378:metabolism; D000077293:Receptor, Transforming Growth Factor-beta Type I; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D043244:Ribonuclease III; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D001616:beta-Galactosidase / Q000378:metabolism
C118115:COTL1 protein, human; D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D005656:Fungal Proteins; D008840:Microfilament Proteins; D015800:Protozoan Proteins; D018125:Receptors, Transforming Growth Factor beta; D011994:Recombinant Proteins; C085568:coactosin protein, Dictyostelium discoideum; D001094:Arachidonate 5-Lipoxygenase; D017346:Protein Serine-Threonine Kinases; D030201:Activin Receptors, Type I; D000077293:Receptor, Transforming Growth Factor-beta Type I; D004722:Endoribonucleases; C118116:dcr-1 protein, C elegans; D043244:Ribonuclease III; D001616:beta-Galactosidase