جستجوی مقالات مرتبط با کلیدواژه « آلوروپوس لیتورالیس » در نشریات گروه « زیست شناسی »

NAC (NAM, ATAF1/2, and CUC2) proteins are the plant-specific transcription factors (TFs) that play roles in diverse developmental processes and stress responses. In the present study, a total of 68 NAC genes were identified in Aeluropus littoralis, a salt secreting halophytic grass, belongs to family Poaceae. By analysis of cis regulatory elements of AlNAC genes promoter, many cis-acting regulatory elements related to growth and development, phytohormone and stresses defense were found in the promoter of AlNAC genes. These hormone-responsive elements, include P-box, TCA element, CGTCA-motif and TGACG-motif, TGA-element, ERE and ABRE, which were associated with gibberellic acid, salicylic acid, jasmonic acid, Auxin, ethylene and abscisic acid response, respectively. For stress responsive elements, TC-rich repeats, ARE, MBS, LTR; and W box, can be noted which are related to defense and stress, anaerobic induction, drought inducibility, low-temperature inducibility, and wound stress, respectively. The different types of cis regulatory elements in the promoter of AlNAC genes and the variability in transcription factors associated with these regulatory elements indicates the important role of these genes in plant development and defense against stress. By analyzing AlNAC32 candidate gene expression using RT-qPCR it was revealed that AlNAC32 was up-regulated under salt, drought and ABA phytohormone stresses in leaf, stem and root tissues, implying its role in multiple abiotic stresses tolerance. These findings provided valuable information for further research on the functions and applications of AlNACs in A. littoralis growth and adaptation to stress.

Hormonal changes of Aeluropus littoralis (Gouan) Parl. halophyte under none- stress, moderate and severe salinity stress condition (0, 250, and 600 mM NaCl, respectively) at four time-courses (3, 6, 12, 24 h) were studied. The results showed that the Abscisic acid (ABA) content increased after one day at all stress levels, however, Gibberellic acid (GA3) levels also significantly decreased under severe stress compared to mild stress. The level of Salicylic acid (SA) decreased slightly compared to the control at the beginning of mild stress condition, but in severe stress, this decrease was more noticeable. Jasmonic acid (JA) content was not different at the first of stress, but with increased stress time, its content increased and in severe stress, it was more than mild stress and in mild stress, it was more than the control. It seems that the plant needs at least 24 hours to respond to stress because in the first time (3 hours) the content of hormones changed compared to the control, which indicates the perception of stress, but in continues the levels of the hormone had limited changes, and within 24 hours, the plant produced a completely different response to its hormonal content than the control. In conclusion, the results of this study will be useful in providing a deeper understanding of the hormonal mechanism of salinity tolerance.

DREB gene family is one large family of transcription factors that plays an important role in regulating plant growth and the response to external environmental stresses. Due to the sequencing of the Aeluropus littoralis halophyte plant genome has provided an excellent opportunity for genome-wide analysis of genes belonging to DREB gene family. In total, 16 non-redundant DREB-encoding genes were identified from the genomic sequences of A. littoralis. In this research, gene structures, phylogenetic relationships, motif compositions and expression profiles of DREB genes under salt stress and recovery conditions were analyzed. The phylogenic construction suggests that the AlDREB gene family was classified into five groups (A1, A2, A4, A5 and A6) in A. littoralis. Gene structure and motif composition revealed that these genes were conservative in each group, suggesting that members of the same group may also have conserved functions. Based on RNA-seq data, AlDREB6.3 and AlDREB6.2 genes were expressed more in root tissue under salinity stress. The least expression level was observed in AlDREB6.4 and AlDREB6.3 genes in leaf tissue under recovery conditions. Result of this study can be applied as a foundation for functional analyses to unravel the biological roles of Aeloropus’ DREB genes.