Overexpression of an NF-YC2 gene confers alkali tolerance to transgenic alfalfa (Medicago sativa L.)

Abstract

Alkaline stress severely limits plant growth and yield worldwide. NF-YC transcription factors (TFs) respond to abiotic stress by activating gene expression. However, the biological function of NF-YC TFs in alfalfa (Medicago sativa L.) is not clear. In our study, an NF-YC2 gene was identified and transgenic plants were obtained by constructing overexpression vector and cotyledon node transformation system in alfalfa. The open reading frame of MsNF-YC2 is 879 bp with 32.4 kDa molecular mass. MsNF-YC2 showed tissue expression specificity and was induced by a variety of abiotic stresses including drought, salt, and alkali stress in alfalfa. Under alkali stress treatment, transgenic plants exhibited higher levels of antioxidant enzyme activities and proline (Pro), correlating with a lower levels of hydrogen peroxide (H2O2), superoxide anion (O2–) compared with wild-type (WT) plants. Transcriptomic results showed that overexpression of MsNF-YC2 regulated the expression of phytohormone signal transduction and photosynthesis-related genes under normal and alkaline stress treatments. These results suggest that the MsNF-YC2 gene plays crucial role enhance alkali adaptation abilities in alfalfa.

<em>Populus euphratica</em> CPK21 Interact with NF-YC3 to Enhance Cadmium Tolerance in Arabidopsis

“…As shown in Figure 7, overexpression of AtNF-YC3 enhanced Cd tolerance in terms of improved root length, fresh weight and membrane stability in Arabidopsis. Here we confirmed for the first time that AtNF-YC3 improves Cd tolerance, although NF-YC transcription factors are required for plant response to ABA (e.g., NF-YC1 in Physcomitrella patens [25]; Cdt-NF-YC1 in bermudagrass [29]) and abiotic stress, such as salt (e.g., NF-YC13 in indica rice [27]; PgNF-YB02, PgNF-YC09, and PgNF-YC07-04 in Panax ginseng [26]), drought (e.g., NF-YC in Amaranthus hypochondriacus [23]), and alkali stress (e.g., NF-YC2 in Medicago sativa [28]). Our data show that PeCPK21 interacts with the transcription factor AtNF-YC3 to limit Cd uptake and enhance ROS degration in transgenic plants.…”

“…The results suggest that AtNF-YC3 increases Cd tolerance by enhancing the activities of antioxidant enzymes in Arabidopsis. Similarly, the NF-YC transcription factor MsNF-YC2 positively regulates the activities of SOD and POD, such that the increased antioxidant enzymes reduce oxidative damage of H2O2 to the cell membrane in transgenic alfalfa [28]. Overexpression of garlic AsNF-YC8 enabled tobacco plants to control ROS levels by activating antioxidant enzymes [20].…”

“…The OsNF-YC13 gene increases salt tolerance in rice plants [27]. MsNF-YC2 overexpression confers alkali tolerance in transgenic alfalfa cultivars [28]. Bermudagrass Cdt-NF-YC1 improves the ability of transgenic rice to tolerate drought and salt stress [29].…”

Genome-Wide Analysis of Nuclear factor-YC Genes in the Tea Plant (Camellia sinensis) and Functional Identification of CsNF-YC6

“…With the in-depth study of NF-Y, it was found that NF-YC can be involved in abiotic stress responses through complex signaling pathways, thus enhancing plant adaptation. For example, overexpression of MsNF-YC2 enhanced alkali tolerance, antioxidant enzyme activity and proline content in transgenic alfalfa (Medicago sativa L.) plants [22]. GmNF-YC14 and Cdt-NF-YC1 can improve the drought and salt tolerance of transgenic soybean and rice through activating ABA-dependent and ABA-independent signaling pathways [10,23].…”