Vol. 13, Issue 9, 3281-3293, September 2002

Calcineurin, a Calcium/Calmodulin-dependent Protein Phosphatase, Is Involved in Movement, Fertility, Egg Laying, and Growth in Caenorhabditis elegans

Jaya Bandyopadhyay,^* Jiyeon Lee,^* Jungsoo Lee,^* Jin Il Lee,^* Jae-Ran Yu,^§ Changhoon Jee,^* Jeong-Hoon Cho,^* Sunki Jung,^* Myon Hee Lee,^¶ Sonia Zannoni,^# Andrew Singson,^# Do Han Kim,^* Hyeon-Sook Koo,^¶ and Joohong Ahnn^*

 ^*Department of Life Science, Kwangju Institute of Science and Technology, Kwangju 500-712, Korea;  ^§Department of Parasitology, College of Medicine, Kon-Kuk University, Chungju 380-710, Korea;  ^¶Department of Biochemistry, College of Science, Yonsei University, Seoul 120-749, Korea; and  ^#Waksman Institute, Rutgers University, Piscataway, New Jersey 08854

Calcineurin is a Ca²⁺-calmodulin-dependent serine/threonine protein phosphatase that has been implicated in various signaling pathways. Here we report the identification and characterization of calcineurin genes in Caenorhabditis elegans (cna-1 and cnb-1), which share high homology with Drosophila and mammalian calcineurin genes. C. elegans calcineurin binds calcium and functions as a heterodimeric protein phosphatase establishing its biochemical conservation in the nematode. Calcineurin is expressed in hypodermal seam cells, body-wall muscle, vulva muscle, neuronal cells, and in sperm and the spermatheca. cnb-1 mutants showed pleiotropic defects including lethargic movement and delayed egg-laying. Interestingly, these characteristic defects resembled phenotypes observed in gain-of-function mutants of unc-43/Ca²⁺-calmodulin-dependent protein kinase II (CaMKII) and goa-1/G_o-protein -subunit. Double mutants of cnb-1 and unc-43(gf) displayed an apparent synergistic severity of movement and egg-laying defects, suggesting that calcineurin may have an antagonistic role in CaMKII-regulated phosphorylation signaling pathways in C. elegans.