A Flower Specific Calcineurin B-Like Molecule (CBL)-Interacting Protein Kinase (CIPK) Homolog in Tomato Cultivar Micro-Tom (&amp;lt;i&amp;gt;Solanum lycopersicum&amp;lt;/i&amp;gt; L.)

Mari Iwaya-Inoue,Takashi Yuasa,Yushi Ishibashi

doi:10.4236/ajps.2012.36091

Abstract

Floral and reproductive organs of higher plants are relatively sensitive to biotic and abiotic stresses compared with the vegetative organs. Calcineurin B-like molecule (CBL) interacting protein kinase (CIPK) has appeared to be involved in acquired tolerance and acclimation under environmental stresses such as salinity, drought and chilling. Semi-quantitative RT-PCR using the vegetative and reproductive organs of tomato Micro-Tom (Solanum lycopersicum L.) at the various developmental stages indicated that SlCIPK2 was expressed specifically in the floral organ. An anti-CIPK specific antibody recognized the recombinant SlCIPK2 specifically and cross-reacted to a CIPK-related polypeptide at a significant level in flower, particularly in stamen. The flower specific CIPK was tightly associated with the microsomes. In vitro pull-down assay of the recombinant SlCIPK2 showed that SlCIPK2 interacts with SlCBLs and stress-responsive transcription factors, SlERF7, SlCBF1 and SlAREB1. The present data suggested that the flower-specific CIPK, SlCIPK2, was involved in calcium signaling in tomato via CBLs and stress tolerance possibly mediated by the stress-responsive transcription factors in stamen.

Highlights

In higher plants, the floral development is well programmed and plays an important role in plant reproduction
A phylogenic tree indicates that the tomato CIPKs and the corresponding Arabidopsis CIPKs formed a distant group from other SNF1-related kinases including SNF1-related protein kinases (SnRKs) I and SnRK II subfamilies and CDPK among the CDPKSNF1 superfamily, as expected (Figure 1(b))
The tomato and Arabidopsis CIPKs formed a monophyletic cluster separated from other clusters of SnRK1 groupe, LeSNF1 and yeast SNF1 [27], and of SnRK2 groupe, SlSnRK2C and AtSnRK2.8, while NtCDPK1 is located as outgroup [12,28]

Summary

Introduction

The floral development is well programmed and plays an important role in plant reproduction. Compared with the vegetative development, the reproductive development is relatively susceptible to environmental stresses such as high temperature, drought and chilling. For an example of tomato races, the fruit production under moderate heat shock is dependent on that genetic background, but there was marginal difference in neither photosynthetic rate nor respiration between the heat tolerant race and the sensitive race, when subjected to high temperature stress. Reduction of tomato fruit yield under high temperature stress was mostly due to failure of pollen development, such as formation of sterile pollen. Proline and sucrose at high concentration, indicating that specific protective mechanisms against heat and/or osmotic stress are involved in development of pollen [3]

Methods

Results

Conclusion