Thigmomorphogenesis: Modifications of calmodulin mRNA and protein levels in tomato plants

Modifications of calmodulin (CaM) mRNA and protein levels were investigated in growing internodes of tomato plants (Lycopersicon esculentum Mill. cv. VFN8) after mechanical stimulation (rubbing treatment). Three cDNAs of CaM (NG, TOMCALM1LE and TOMCALM2LE) were isolated using RT-PCR and subsequently cloned. The increase in the three mRNAs was systematically observed after mechanical stimulation. In contrast to NG and TOMCALM1-LE, TOMCALM2-LE mRNA was found to be particularly important in control plants. In addition, the CaM protein level was analysed by Western blot and ELISA a ssays. In planta, a significant increase in CaM protein was observed after rubbing treatment.