Lilium pumilum stress-responsive NAC transcription factor LpNAC17 enhances salt stress tolerance in tobacco

Abstract

Lilium pumilum is a perennial herb with ornamental edible and medicinal value. It is an excellent wild germplasm resource with wide distribution and strong resistance. The NAC family of transcription factors is unique to higher plants. The NAC family plays a regulatory role in plant growth and development and participates in plant responses to biotic and abiotic stresses. The LpNAC17 gene of L. pumilum was cloned and transformed into tobacco to investigate the response of transgenic tobacco to salt stress. The results showed that the net photosynthetic rate and contents of chlorophyll in LpNAC17 over-expressed tobacco were higher than those in the control plants, while the stomatal conductance, transpiration rate and intercellular CO2 concentration were lower than those in the controls. The activity of superoxide dismutase, peroxidase, catalase, and the content of proline in LpNAC17 over-expressed tobacco were higher than those in the controls, while the content of malondialdehyde, superoxide anion, and hydrogen peroxide were lower than that in the control. Nitro-blue tetrazolium staining and 3,3′-diaminobenzidine tissue localization showed that the contents of O2- and H2O2 in transgenic tobacco was lower than in the controls. The expression levels of NtSOD, NtPOD, NtCAT, NtHAK1, NtPMA4, and NtSOS1 in the transgenic tobacco were higher than those in the controls. Therefore, this study provides a gene source for molecular breeding of salt-tolerant plants through genetic engineering, and lays a foundation for further research on salt-tolerant Lily.

Genome-Wide Investigation of the NAC Transcription Factor Family in Apocynum venetum Revealed Their Synergistic Roles in Abiotic Stress Response and Trehalose Metabolism

“…The number of AvNAC gene family member was the same as in Vitis vinifera (74) [30], more than in Lagerstroemia indica (21) [31] and Lolium perenne (72) [1] but less than in O. sativa (151) [8], Z. mays (152) [9], Vigna radiata L. (81) [28] and Passiflora edulis (105) [32]. The variation may be related to gene duplication during the evolution of the species.…”

“…These abiotic stresses limit the area of arable lands for agriculture and negatively affect crop productivity. To resist these stresses, plants have evolved complex and sophisticated regulatory pathways to sense and adapt to these stresses in a timely manner, which are regulated by promoting the expression of stress-responsive genes [1]. Transcription factors are the core of regulating gene expression by specifically binding to cis-elements of the target gene promoter to regulate the expression of downstream genes [2].…”

“…et Zucc.) in Arabidopsis enhanced salt tolerance, and SlNAC10 (from Suaeda liaotungensis) in Arabidopsis in addition to salt enhanced drought tolerance [1,19,20]. Additionally, the NAC transcription factor ATAF1 (Arabidopsis Transcription Activation Factor 1) was found to respond to carbon starvation by participating in trehalose metabolism.…”

WRKY22 Transcription Factor from Iris laevigata Regulates Flowering Time and Abiotic Stress Resistance

“…A Li-6400 portable photosynthesis instrument was used to quantify various photosynthetic parameters including net photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate. Three individual plants were randomly selected from each line (transgenic, empty vector control, and wild-type plants), and the 3rd and 4th leaf were used for measurement [63]. The Li-6400 instrument was calibrated before taking measurements and data was recorded after the reading was stable.…”

“…Five measurements were taken for each leaf. The total chlorophyll content was determined as described, using the acetone extraction method [63].…”