1.
The WUSCHELa (PtoWUSa) is Involved in Developmental Plasticity of Adventitious Root in Poplar.
Li, J, Jia, H, Sun, P, Zhang, J, Xia, Y, Hu, J, Wang, L, Lu, M
Genes. 2020;(2)
Abstract
WUSCHEL-RELATED HOMEOBOX (WOX) transcription factors play critical roles in cell fate determination during plant development. As the founding member of the WOX family, WUSCHEL (WUS) is characterized for its role in maintaining stem cell in meristem. In this study, we investigated the function of Populus tomentosa WUSCHELa (PtoWUSa) in adventitious roots (ARs) in poplar. Expression profile analysis showed that PtoWUSa was not only expressed in shoot apical meristem and stem, but also expressed in ARs. Ectopic expression of PtoWUSa in Arabidopsis resulted in shortened primary root, as well as agravitropism and multiple branches. Overexpression of PtoWUSa in poplar increased the number of ARs but decreased their length. Moreover, the AR tip and lateral root tip became larger and swollen. In addition, the expression of auxin transporter genes PIN-FORMED were downregulated in ARs of transgenic plant. Taken together, these results suggest that PtoWUSa could be involved in AR development in poplar through regulating the polar auxin transport in ARs.
2.
Genome-wide transcriptomic analysis of a desert willow, Salix psammophila, reveals the function of hub genes SpMDP1 and SpWRKY33 in drought tolerance.
Jia, H, Zhang, J, Li, J, Sun, P, Zhang, Y, Xin, X, Lu, M, Hu, J
BMC plant biology. 2019;(1):356
Abstract
BACKGROUND Drought is a major environmental constraint to plant growth, development and productivity. Compared with most willows that are generally susceptible to drought, the desert willow Salix psammophila has extraordinary adaptation to drought stress. However, its molecular basis of drought tolerance is still largely unknown. RESULTS During polyethylene glycol 6000 (PEG 6000)-simulated drought stress, we found that the osmotic adjustment substances were accumulated and the antioxidant enzyme activities were enhanced in S. psammophila roots. A total of 8172 differentially expressed genes were identified in roots of S. psammophila through RNA-Sequencing. Based on K-means clustering, their expression patterns were classified into nine clusters, which were enriched in several stress-related processes including transcriptional regulation, response to various stresses, cell death, etc. Moreover, 672 transcription factors from 45 gene families were differentially expressed under drought stress. Furthermore, a weighted gene co-expression network was constructed, and eight genes were identified as hub genes. We demonstrated the function of two hub genes, magnesium-dependent phosphatase 1 (SpMDP1) and SpWRKY33, through overexpression in Arabidopsis thaliana. Overexpression of the two hub genes enhanced the drought tolerance in transgenic plants, suggesting that the identification of candidate drought tolerance genes in this study was highly efficient and credible. CONCLUSIONS Our study analyzed the physiological and molecular responses to drought stress in S. psammophila, and these results contribute to dissect the mechanism of drought tolerance of S. psammophila and facilitate identification of critical genes involved in drought tolerance for willow breeding.
3.
[The interaction of MADS-box transcription factors and manipulating fruit development and ripening].
Liu, JH, Xu, BY, Zhang, J, Jin, ZQ
Yi chuan = Hereditas. 2010;(9):893-902
Abstract
The proteins encoded by MADS-box genes are a large number of transcription factors, which control plant growth and development by forming homo- or hetero-dimers. Here, we reviewed recent researches on the interactions of MADS-box transcription factors and manipulating fruit development and ripening, which will help us to understand the mechanism of MADS-box transcription factors and provide references for further investigating the functions of MADS-box genes on fruit development and ripening.
4.
[Mechanisms of heavy metal cadmium tolerance in plants].
Zhang, J, Shu, WS
Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology. 2006;(1):1-8
Abstract
Cadmium (Cd) is a strongly phytotoxic heavy metal, which inhibits plant growth and even leads to plant death. The main symptoms of Cd(2+) toxicity to plants are stunting and chlorosis. Plant has developed some functions for Cd(2+) tolerance, which include cell wall binding, chelation with phytochelatins (PCs), compartmentation of Cd(2+) in vacuole, and enrichment in leaf trichomes. However, Cd(2+) tolerance in plant is more likely involved in an integrated network of multiple response processes than several isolated functions cited above. In the network, the processes of sulfur metabolism, antioxidative response, and Cd(2+) transport across plasma and vacuole membrane in plant are closely related with Cd(2+) tolerance in plant. The processes of sulfur uptake, assimilation and sequential sulfur metabolism in plant respond to Cd(2+) stress. The expression of sulfur transporters with varied affinity was changed in different ways under Cd(2+) stress, and the high expression of ATP sulfurylase (APS) and adenosine 5' phosphosulfate reductase (APR), which may help to keep the supply of S(2-) for cysteine (Cys) synthesis. The efficiency of Cys synthesis may function in Cd(2+) detoxification, and the up-regulated expression of Ser acetyltransferase (SAT) and O-acetyl-ser (thiol)-lyase (OASTL) has been found in some Cd(2+) treated plants. Reduced glutathione (GSH) is an important antioxidant and the precursor of PCs, glutamylcysteine synthetase (GCS) and glutathione synthetase (GS) catalyze GSH synthesis from Cys, overexpression of the two enzymes can improve Cd(2+) tolerance in plant. PCs are more important Cd(2+) chelators than metallothioneins (MTs) in plants, and the expression of phytochelatin synthase (PCS) responds to Cd(2+) stress. Plant antioxidative system also contributes to Cd(2+) tolerance. The antioxidative response to Cd(2+)-induced oxidative stress varies in different plants and tissues and is also Cd(2+) concentration dependent, and the Cd hyperaccumulator plants show strong tolerance to oxidative stress. Some genes encoded metal transporters with Cd(2+) substrate specificity at plasma and vacuole membranes, which have been isolated and characterized in recent years. These genes play critical roles in Cd(2+) translocation, allocation, and compartmentation in plants. Despite the great progresses made in the field in recent years, there are still some issues which need further exploration, such as the detail of signal transduction and the responses of gene regulation to Cd(2+), the rhizosphere activation and root adsorption to soil Cd(2+), Cd(2+) trafficking in xylem and phloem, Cd(2+) translocation to fruit and seed, and the possible presence of a high-affinity Cd(2+) transporter in Cd hyperaccumulators.