Clone And Time-space Expression Analysis Of GmCOL Genes

Soybean is a typical short-day plant. To study on the molecular mechanism of triggering soybean flowering in short day is of great significance both in theory and practice. Many studies showed that CONATANS (CO) plays a key role in the flowering photoperiod pathway, however, the knowledge about soybean CONSTANS and CONSTANS-LIKE protein is rather limited until now. Few reports can be currently available on their sequences, structures and functions in inducing flowering in different day length. To understand the photoperiod sensitivity molecular mechanism , we searched GmCOL gene in soybean. The reaults were as follows:According to the bioinformatics information of proteins of both Arabidopsis CO family and soybean homologues, we predicted 23 GmCOLs genes in soybean genome, which located on different regions of 16 chromosomes. Based on classification criteria of the CO gene family in Arabidopsis, soybean GmCOLs can also be divided into three groups, namely group I (2 B-boxes), group II (1 B-box), group III (1 B-box and a lower conservative zinc finger), three groups contain a CCT functional domain. GmCOL13 is the gene nearest to AtCO in sequence, GmCOL5 shares highly homologous with OsHd1. The data provided another line of evidence that CO gene is highly conserved across plants during evolutional progress.In this study 10 CONSTANS-LIKE (GmCOLs) genes were cloned from soybean“Kennong 18”, in which GmCOL8-12 were employed as the main objective and checked their expression in time and space. The results from quantitative real time RT-PCR (qPCR) showed that the mRNA of GmCOL8-11 displayed significant circadian expressions in short day conditions. GmCOL8 and GmCOL10 had similar expression patterns and peaked their expressions at dawn and 6h after light (Zeitgeber Time 0h and 6h). GmCOL8-12 expressed in various leaves at different developmental stages.T2 plants of overexpression of GmCOL8 in Arabidopsis wild type Col-4 background appeared segregation phenotypes of the wild type and early flowering in short day conditions. T1 generation of overexpression of GmCOL10 in Arabidopsis co-2 mutant background showed early senescence in long day conditions. The results suggested that the GmCOLs genes functioned not only in flowering, but also other important physiological processes.