Expression Analysis Of Calmodulin And Calmodulin-like Gene Family And Ionome Analysis Of Cotton Fiber

As a second messenger, calcium signaling is involved in many physiological and biochemical processes in plants. Calmodulin(Ca M) and Calmodulin-like(CML), two important calcium receptors, play key roles in calcium signaling transduction. Our laboratory has confirmed that Gh Ca M7 plays an important role in the initiation and elongation of fiber, but there has been no systematic study on the expression analysis of Ca M and CML genes in cotton. Mineral elements are the important material basis for plant growth and development. Ionome analysis of cotton fiber provides a new perspective for finding the factor that affect the development of cotton fiber. The main results are as follow:According to homology search, 5 Ca M genes and 60 CML genes were identified from the genome of G. raimondii. They were divided into 9 subgroups by phylogenetic analysis. Furthermore, sequence alignment analysis confirmed that Gr Ca Ms contained one or two introns, however, Gr CMLs intron numbers varied and many of them had no intron. The expression patterns of Gr Ca Ms were also investigated, which showed that they were preferentially expressed in fiber elongation stage. Inconsistent with Gr Ca Ms, many of Gr CMLs were expressed at low levels in certain tissue, but high in development of cotton. The data implied that Gr Ca Ms and Gr CMLs might be involved in cotton growth and development. To investigate whether Gr Ca Ms and Gr CMLs were involved in plant stress response, q RT-PCR was used. The outcomes verified that the large number of Gr Ca Ms and Gr CMLs were iuduced by Na Cl, PEG and Cold, which suggest that some upland cotton genes which were homoelogs with Gr Ca M and Gr CML play a role in multiple abiotic stresses. Different phytohormones(ABA, JA and SA) treatments in cotton showed that these phytohormones regulated the expression of upland cotton genes which were homoelogs with Gr Ca M and Gr CML.We analyzed ionomes of cotton fiber and ovule by using ICP-MS. The results showed that the concentrations of K, P, Ca, Mg, B, Mn and other ions in fiber were higher than that of in ovule during fiber rapid elongation period, suggesting that these ions might be one player accounting for fiber rapid elongation.