Developmental regulation of the gene for chimeric calcium/calmodulin-dependent protein kinase in anthers

Abstract

Chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) was cloned from developing anthers of lily (Lilium longiflorum Thumb. cv. Nellie White) and tobacco (Nicotiana tabacum L. cv. Xanthi). Previous biochemical characterization and structure/function studies had revealed that CCaMK has dual modes of regulation by Ca(2+) and Ca(2+)/calmodulin. The unique structural features of CCaMK include a catalytic domain, a calmodulin-binding domain, and a neural visinin-like Ca(2+)-binding domain. The existence of these three features in a single polypeptide distinguishes it from other kinases. Western analysis revealed that CCaMK is expressed in a stage-specific manner in developing anthers. Expression of CCaMK was first detected in pollen mother cells and continued to increase, reaching a peak around the tetrad stage of meiosis. Following microsporogenesis, CCaMK expression rapidly decreased and at later stages of microspore development, no expression was detected. A tobacco genomic clone of CCaMK was isolated and transgenic tobacco plants were produced carrying the CCaMK promoter fused to the beta-glucuronidase reporter gene. Both CCaMK mRNA and protein were detected in the pollen sac and their localizations were restricted to the pollen mother cells and tapetal cells. Consistent results showing a stage-specific expression pattern were obtained by beta-glucuronidase analysis, in-situ hybridization and immunolocalization. The stage- and tissue-specific appearance of CCaMK in anthers suggests that it could play a role in sensing transient changes in free Ca(2+) concentration in target cells, thereby controlling developmental events in the anther.

Fungal Symbiosis in Rice Requires an Ortholog of a Legume Common Symbiosis Gene Encoding a Ca2+/Calmodulin-Dependent Protein Kinase

“…harvard.edu/tgi), from which two of the six ESTs in TC290169 were from flower tissue, while the remaining four came from root tissue. The higher level expression of OsDMI3 in flower organs was in contrast to the expression pattern reported in M. truncatula (Levy et al, 2004), but consistent with that observed for the CCaMK genes in non-legumes such as lily (Lilium longiflorum) and tobacco (Nicotiana tabacum; Poovaiah et al, 1999). The expression level of OsDMI3 in rice roots was not significantly affected by mycorrhization (Fig.…”

Rhizobial and Fungal Symbioses Show Different Requirements for Calmodulin Binding to Calcium Calmodulin–Dependent Protein Kinase in Lotus japonicus

“…This result supports the view that CaM binding to CaMBD is required for the negative regulation of CCaMK. It has also been reported that lily and tobacco (Nicotiana tabacum) CCaMKs are expressed in anthers (Patil et al, 1995;Liu et al, 1998;Poovaiah et al, 1999), and increased expression of both CCaMK and CaM were detected in pollen cells of tobacco (Poovaiah et al, 1999). These results imply the possibility that nonleguminous CCaMKs are also involved in reproductive stages in which CCaMK and CaM interaction is required.…”

“…Based on the characterization of CCaMK, including in vitro phosphorylation and ligand binding assays with a CCaMK deletion series, a working model for CCaMK activation has been proposed (Sathyanarayanan et al, 2000). Additional studies have been made of the biochemical and expression properties of CCaMK proteins in nonlegumes (Liu et al, 1998;Poovaiah et al, 1999;Pandey and Sopory, 2001); however, the detailed mechanism of CCaMK activation in response to cytosolic Ca 2+ signals remains unclear.…”

Recent Advances in Calcium/Calmodulin-Mediated Signaling with an Emphasis on Plant-Microbe Interactions

“…Tobacco (Nicotiana tabacum) CCaMK was indicated to play a role in controlling the development of anther (Poovaiah et al, 1999), and pea (Pisum sativum) CCaMK was up-regulated in roots in response to low temperature and salt treatment (Pandey et al, 2002). Recent results showed that CCaMK from maize (Zea mays; ZmCCaMK) and rice (OsCCaMK) both play important roles in abscisic acid-induced antioxidant protection (Ma et al, 2012;Shi et al, 2012).…”