Tyrphostins are inhibitors of guanylyl and adenylyl cyclases

被引:36
作者
Jaleel, M [1 ]
Shenoy, AR [1 ]
Visweswariah, SS [1 ]
机构
[1] Indian Inst Sci, Dept Mol Reprod Dev & Genet, Bangalore 560012, Karnataka, India
关键词
D O I
10.1021/bi036234n
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Guanylyl cyclase C (GC-C), the receptor for guanylin, uroguanylin, and the heat-stable enterotoxin, regulates fluid balance in the intestine and extraintestinal tissues. The receptor has an extracellular domain, a single transmembrane spanning domain, and an intracellular domain that harbors a region homologous to protein kinases, followed by the C-terminal guanylyl cyclase domain. Adenine nucleotides can regulate the guanylyl cyclase activity of GC-C by binding to the intracellular kinase homology domain (KHD). In this study, we have tested the effect of several protein kinase inhibitors on GC-C activity and find that the tyrphostins, known to be tyrosine kinase inhibitors, could inhibit GC-C activity in vitro. Tyrphostin A25 (AG82) was the most potent inhibitor with an IC50 of similar to15 muM. The mechanism of inhibition was found to be noncompetitive with respect to both the substrate MnGTP and the metal cofactor. Interestingly, the activity of the catalytic domain of GC-C (lacking the KHD) expressed in insect cells was also inhibited by tyrphostin A25 with an IC50 of similar to5 muM. As with the full-length receptor, inhibition was found to be noncompetitive with respect to MnGTP. Inhibition was reversible, ruling out a covalent modification of the receptor. Structurally similar proteins such as the soluble guanylyl cyclase and the adenylyl cyclases were also inhibited by tyrphostin A25. Evaluation of a number of tyrphostins allowed us to identify the requirement of two vicinal hydroxyl groups in the tyrphostin for effective inhibition of cyclase activity. Therefore, our studies are the first to report that nucleotide cyclases are inhibited by tyrphostins and suggest that novel inhibitors based on the tyrphostin scaffold can be developed, which could aid in a greater understanding of nucleotide cyclase structure and function.
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收藏
页码:8247 / 8255
页数:9
相关论文
共 44 条
[1]   Homologous desensitization of the human guanylate cyclase C receptor - Cell-specific regulation of catalytic activity [J].
Bakre, MM ;
Ghanekar, Y ;
Visweswariah, SS .
EUROPEAN JOURNAL OF BIOCHEMISTRY, 2000, 267 (01) :179-187
[2]  
BARZU O, 1994, PROG NUCLEIC ACID RE, V49, P241
[3]  
BERS DM, 1994, METHOD CELL BIOL, V40, P3
[4]   Guanylyl cyclase C receptor: Regulation of catalytic activity by ATP [J].
Bhandari, R ;
Suguna, K ;
Visweswariah, SS .
BIOSCIENCE REPORTS, 1999, 19 (03) :179-188
[5]   Functional inactivation of the human guanylyl cyclase C receptor: Modeling and mutation of the protein kinase-like domain [J].
Bhandari, R ;
Srinivasan, N ;
Mahaboobi ;
Ghanekar, Y ;
Suguna, K ;
Visweswariah, SS .
BIOCHEMISTRY, 2001, 40 (31) :9196-9206
[6]   Tyrosine phosphorylation of the human guanylyl cyclase C receptor [J].
Bhandari, R ;
Mathew, R ;
Vijayachandra, K ;
Visweswariah, SS .
JOURNAL OF BIOSCIENCES, 2000, 25 (04) :339-346
[7]  
CHINKERS M, 1991, J BIOL CHEM, V266, P4088
[8]  
CHINKERS M, 1992, J BIOL CHEM, V267, P18589
[9]   THE PROTEIN-KINASE DOMAIN OF THE ANP RECEPTOR IS REQUIRED FOR SIGNALING [J].
CHINKERS, M ;
GARBERS, DL .
SCIENCE, 1989, 245 (4924) :1392-1394
[10]   Cytoplasmic domains mediate the ligand-induced affinity shift of guanylyl cyclase C [J].
Deshmane, SP ;
Parkinson, SJ ;
Crupper, SS ;
Robertson, DC ;
Schulz, S ;
Waldman, SA .
BIOCHEMISTRY, 1997, 36 (42) :12921-12929