High impact information on tpa-1

• The predicted amino acid sequence revealed that the predicted tpa-1 protein sequence is highly similar to protein kinase C molecules from various animals, including man [1].
• A genomic fragment that constitutes a portion of the tpa-1 gene was cloned by Tc1 transposon tagging and was used as a probe to screen a nematode complementary DNA library [1].
• Molecular and pharmacological studies in vitro suggest that protein kinase C (PKC) family members play important roles in intracellular signal transduction [2].
• DKF-1 phosphorylation and activation are unaffected when PKC activity is eliminated by inhibitors [3].
• However, the modes of action of Munc-18 and PKC in vesicle transport have not been clarified [4].

Biological context of tpa-1

• The gene tpa-1 on chromosome IV of the nematode Caenorhabditis elegans plays a major and definitive role in the adversary action of tumour-promoting phorbol esters, which induce growth arrest and locomotory distress in the animal [5].
• The tpa-1 gene of Caenorhabditis elegans encodes two proteins similar to Ca(2+)-independent protein kinase Cs: evidence by complete genomic and complementary DNA sequences of the tpa-1 gene [5].
• Therefore, the phosphorylation by PKC may play a physiological role in the regulation [6].
• On the other hand, protein kinase C (PKC) stimulates Ca2+-dependent exocytosis in various types of secretory cells [4].

Anatomical context of tpa-1

• Here, we show that recombinant Munc-18 is phosphorylated by conventional PKC in a Ca2+- and phospholipid-dependent manner in a cell-free system [4].

Associations of tpa-1 with chemical compounds

• One of the tpa-1 isoforms, which is expressed in vulval cells, is found to play a role in nicotine-induced adaptation [7].
• The Caenorhabditis elegans Unc-13 protein is a novel member of the phorbol ester receptor family having a single cysteine-rich region with high homology to those present in protein kinase C (PKC) isozymes and the chimaerins [8].
• It thus appears that Ca(2+) and PKC are critically involved in GAR-3b-mediated cAMP formation [9].
• Inhibition of protein kinase C (PKC) by chronic treatment with phorbol 12-myristate 13-acetate (PMA) or by GF109203X decreased carbachol-stimulated cAMP production by as much as 68% [9].

Regulatory relationships of tpa-1

• Finally, PKC1A and PKC1B mRNA levels are differentially regulated by phorbol esters in a process that may involve the participation of another PKC isoform that is analogous to mammalian PKC delta [10].

Other interactions of tpa-1

• The gene tpa-1 mapped near the marker gene dpy-9 on chromosome IV [11].

Analytical, diagnostic and therapeutic context of tpa-1

• The gene was deduced to code for a protein kinase C (PKC) homologue by molecular cloning [5].

References