Two SiCKX genes, including SiCKX1 and SiCKX10, were examined in all eight tissues. EST numbers of SiCKX9 were the lowest, up to 4 ( Table 3). The above results suggest that some as yet unidentified tissue-specific factors may affect the expression of CKX genes. Real-time PCR analysis in this work showed that all 11 SiCKX genes were significantly induced by exogenous 6-BA in germinating embryos ( Fig. 6). This is consistent with other reports
of applying exogenous CKs or 6-BA resulting in enhancement of CKX expression levels [31] and [57]. In Fig. 4, four protein pairs (SiCKX1 and SiCKX3, SiCKX5 and SiCKX8, SiCKX2 and SiCKX4, and SiCKX10 and SiCKX11) formed distinct subgroups in the phylogenetic tree, suggesting that each protein pair may share the same biological function. However, only mTOR cancer four genes (SiCKX1, SiCKX3, SiCKX5, and SiCKX8) were obviously induced under salt and 20% PEG-6000 stresses. This finding indicates that SiCKX genes may have distinct and partially overlapping expression patterns related to their diverse roles. Further selleck work is required in order to illuminate the detailed functions of each CKX gene in abiotic stress. In summary, 11 foxtail millet CKX genes were identified in whole genome analysis. The results of SiCKX gene chromosomal location, expansion pattern, motif
distribution, evolutionary relationship, cis-element analysis in promoter regions, and expression profiles under various abiotic treatments provided useful information for CKX research in foxtail millet and other plants. This study was supported by the project of the Modern Seed Industry Enterprise Science and Technology Development of PAK6 Shandong Province, China (SDKJ2012QF003). “
“Transcription factors, which exist in all living organisms, are essential for the regulation of gene expression. WRKY transcription factors, a family of regulatory genes, were first identified in plants [1], [2] and [3]. In WRKY family proteins, a 60 amino acid region is highly conserved among family members. It includes the conserved WRKYGQK
sequence followed by one of the two types of zinc finger motifs, the C2H2 and C2–HC types [4]. All known WRKY proteins can be divided into three groups (group I, II, and III) based on the number of WRKY domains and the types of zinc finger motif. Two WRKY domains can be found in group I proteins, whereas a single domain is present in group II and group III proteins. Generally, group I and group II proteins share the same C2H2-type zinc finger motif (C–X4–5–C–X22–23–H–X1–H). In group III, WRKY domains contain a C2–HC-type motif (C–X7–C–X23–H–X1–C) [4]. Group II is further classified into several subgroups based on their phylogenetic clades [4], [5] and [6]. In plants, WRKY proteins form a large family of transcription factors and are known to function in response to various physiological processes.