Functional Analysis Of Maize Nuclear Factor ZmNF-YC14 In Stress Resistance And Flowering Of Arabidopsis Thaliana

Maize is an important food crop,but its yield is easily affected by the environment.When plants are in an adverse environment(such as high temperature,salt damage,etc.),many physiological activities in the plant body will be affected,and the main manifestation in ER is: protein misfolding or protein folding reaction,resulting in endoplasmic reticulum stress.To maintain cell homeostasis,the unfolded protein response(UPR)is initiated.The unfolded protein response(UPR)is a stress relieving mechanism for monitoring protein folding in the cellular secretory pathway.NF-Y nuclear factor is widely involved in plant stress response,flowering and regulation of grain development.More than 50 NF-Y genes have been identified in maize,but few studies have been conducted on their function and mechanism in resistance regulation.in previous studies,our research group found that overexpression of ZmNF-YC14 gene in Arabdiopsis,which was induced by abiotic stress.In this study,we cloned ZmNF-YC14 gene and its function was preliminarily analyzed in Arabidopsis thaliana.The main results were as follows:1.Analysis of maize seedlings after stress treatment showed that ZmNF-YC14 gene was expressed under endoplasmic reticulum stress and ABA induction.Tissue specificity analysis showed that ZmNF-YC14 gene was expressed in each organ of maize.with the highest expression in maize leaves,the second highest in roots,embryos and endosperm,and the lowest in stems,spikels and tassels.The analysis of GFP fusion protein and yeast self-activation showed that Zm NF-YC14 was mainly located in the nucleus and had certain transcriptional activation ability.2.The overexpression of ZmNF-YC14 gene in Arabidopsis thaliana enhanced the plant's ability to withstand endoplasmic reticulum stress.Under endoplasmic reticulum stress,overexpressed plants had more green-large plants and fewer yellow-small plants than wild-type plants.Moreover,overexpression of ZmNF-YC14 gene enhanced the growth ability of primary root,At the same time,the over-expression of ZmNF-YC14 gene increased the expression level of related genes in the unfolded protein response pathway in plant.3.The overexpression of ZmNF-YC14 gene in Arabidopsis thaliana enhanced the plant's sensitivity to ABA.After ABA treatment,the primary rooting growth of overexpressed plants was inhibited to a greater extent than that of wild type,and the expression level of genes related to protein folding pathway was also increased.4.The overexpression of ZmNF-YC14 gene delayed the flowering period of Arabidopsis thaliana under the condition of long sunshine,and changed the overall structure of the inflorescence,such as the growth time of inflorescence I,the number of primary branches and the number of scones,etc.It also affected the expression of key genes in flowering regulation.5.The involvement of ZmNF-YC14 gene in flowering regulation may depend on GA pathway.After exogenous GA application,the late flower phenotype of overexpressed plants was partially recovered,and the number of primary branches of plants was further increased,and the expression of flowering regulatory genes under GA pathway was affected.