Changes in ABA, IAA and JA levels during calyx, fruit and leaves development in cape gooseberry plants (Physalis peruviana L.).

Changes in abscisic acid (ABA), indole-3-acetic acid (IAA) and jasmonic acid (JA) content in developing calyx, fruits and leaves of Physalis peruviana L. plants were analysed. Plant hormones have been widely studied for their roles in the regulation of various aspects related to plant development and, in particular, into their action during development and ripening of fleshly fruits. The obtained evidences suggest that the functions of these hormones are no restricted to a particular development stage, and more than one hormone is involved in controlling various aspects of plant development. Our results will contribute to understand the role of these hormones during growth and development of calyx, fruits and leaves in cape gooseberry plants. This work offers a good, quickly and efficiently protocol to extract and quantify simultaneously ABA, IAA and JA in different tissues of cape gooseberry plants.

Casein kinase activity in etiolated Cucumis sativus cotyledons.

Two calcium- and light-dependent protein kinases have been reported in etiolated Cucumis sativus cotyledons (Vidal et al. 2007). In the present work, we studied casein kinase (CK) activity in etiolated cucumber cotyledons of in-gel and in vitro kinase assays, using specific CK inhibitors, and ATP and GTP as phosphate donors. Two proteins with CK activity were detected in both casein gels and autophosphorylation assays. One of them, with a molecular mass of approximately 36 kDa, showed biochemical CK1 characteristics: it was inhibited by specific CK1 inhibitors and only used ATP as phosphate donor. The second, with a molecular mass of approximately 38 kDa, had CK2 characteristics; it used both ATP and GTP as phosphate donors, was inhibited by all specific CK2 inhibitors, and was recognized by a polyclonal antibody directed against the alpha catalytic subunit of a CK2 from tobacco. The kinase activity of the CK2 detected in etiolated cucumber cotyledons showed circadian rhythmicity in both in vitro and in-gel casein phosphorylation and in autophosphorylation assays. Thus, our results suggest that the CK2 of approximately 38 kDa could be related to the circadian oscillator of C. sativus cotyledons.