Dorsal switch protein 1(DSP1), a mammalian homolog of HMGB1, is firstly identified as a dorsal co-repressor in 1994. DSP1 contains HMG-box domain and functions as a transcriptional regulator in Drosophila melanogaster. It plays a crucial role in embryonic development, particularly in dorsal-ventral patterning during early embryogenesis, through the regulation of gene expression. Moreover, DSP1 is implicated in various cellular processes, including cell fate determination and tissue differentiation, which are essential for embryonic development. While the function of DSP1 in embryonic development has been relatively well-studied, its role in the adult Drosophila brain remains less understood. In this study, we investigated the role of DSP1 in the brain by using neuronal-specific DSP1 overexpression flies. We observed that climbing ability and life span are decreased in DSP1-overexpressed flies. Furthermore, these flies demonstrated neuromuscular junction (NMJ) defect, reduced eye size and a decrease in tyrosine hydroxylase (TH)-positive neurons, indicating neuronal toxicity induced by DSP1 overexpression. Our data suggest that DSP1 overexpression leads to neuronal dysfunction and toxicity, positioning DSP1 as a potential therapeutic target for neurodegenerative diseases.

CONCLUSIONS: TaMYB44-5A identified as a transcription factor negatively regulates drought tolerance in transgenic Arabidopsis. Drought can severely reduce yields throughout the wheat-growing season. Many studies have shown that R2R3-MYB transcription factors are involved in drought stress responses. In this study, the R2R3-MYB transcription factor MYB44-5A was identified in wheat (Triticum aestivum L.) and functionally analyzed. Three homologs of TaMYB44 were isolated, all of which localized to the nucleus. Overexpression of TaMYB44-5A reduced drought tolerance in Arabidopsis thaliana. Further analysis showed that TaMYB44-5A reduced the sensitivity of transgenic Arabidopsis to ABA. Genetic and transcriptional regulation analyses demonstrated that the expression levels of drought- and ABA-responsive genes were downregulated by TaMYB44-5A, and TaMYB44-5A directly bound to the MYB-binding site on the promoter to repress the transcription level of TaRD22-3A. Our results provide insights into a novel molecular pathway in which the R2R3-MYB transcription factor negatively regulates ABA signaling in response to drought stress.

Robustness is the reproducible development of a phenotype despite stochastic noise. It often involves tradeoffs with other performance metrics, but the mechanisms underlying such tradeoffs were largely unknown. An Arabidopsis flower robustly develops four sepals from four precisely positioned auxin maxima. The development related myb-like 1 (drmy1) mutant generates noise in auxin signaling that disrupts robustness in sepal initiation. Here, we find that increased expression of CUP-SHAPED COTYLEDON1 (CUC1), a boundary specification transcription factor, in drmy1 underlies this loss of robustness. CUC1 surrounds and amplifies stochastic auxin noise in drmy1 to form variably positioned auxin maxima and sepal primordia. Removing CUC1 from drmy1 provides time for noisy auxin signaling to resolve into four precisely positioned auxin maxima, restoring robust sepal initiation. However, removing CUC1 decreases the intensity of auxin maxima and slows down sepal initiation. Thus, CUC1 increases morphogenesis speed but impairs robustness against auxin noise. Further, using a computational model, we find that the observed phenotype can be explained by the effect of CUC1 in repolarizing PIN FORMED1 (PIN1), a polar auxin transporter. Lastly, our model predicts that reducing global growth rate improves developmental robustness, which we validate experimentally. Thus, our study illustrates a tradeoff between speed and robustness during development.

BACKGROUND: JUB1, a NAC domain containing hydrogen peroxide-induced transcription factor, plays a critical role in plant immunity. Little is known about how JUB1 responds to leaf rust disease in wheat. Recent discoveries in genomics have also unveiled a multitude of sORFs often assumed to be non-functional, to argue for the necessity of including them as potential regulatory players of translation. However, whether methylation on sORFs spanning the 3\'UTR of regulatory genes like JUB1 modulate gene expression, remains unclear.
RESULTS: In this study, we identified the methylation states of two sORFs in 3\'UTR of a homologous gene of JUB1 in wheat, TaJUB1-L, at cytosine residues in CpG, CHH and CHG sites at different time points of disease progression in two near-isogenic lines of wheat (HD2329), with and without Lr24 gene during leaf rust pathogenesis. Here, we report a significant demethylation of the CpG dinucleotides occurring in the sORFs of the 3\'UTR in the resistant isolines after 24 h post-infection. Also, the up-regulated gene expression observed through RT-qPCR was directly proportional to the demethylation of the CpG sites in the sORFs.
CONCLUSIONS: Our findings indicate that TaJUB1-L might be a positive regulator in providing tolerance during leaf rust pathogenesis and cytosine methylation at 3\'UTR might act as a switch for its expression control. These results enrich the potential benefit of conventional methylation assay techniques for unraveling the unexplored enigma in epigenetics during plant-pathogen interaction in a cost-effective and confidentially conclusive manner.

Plants are often exposed to biotic or abiotic stress, which can seriously impede their growth and development. In recent years, researchers have focused especially on the study of plant responses to biotic and abiotic stress. As one of the most widely planted grapevine rootstocks, \'Beta\' has been extensively proven to be highly resistant to stress. However, further research is needed to understand the mechanisms of abiotic stress in \'Beta\' rootstocks. In this study, we isolated and cloned a novel WRKY transcription factor, VhWRKY44, from the \'Beta\' rootstock. Subcellular localization analysis revealed that VhWRKY44 was a nuclear-localized protein. Tissue-specific expression analysis indicated that VhWRKY44 had higher expression levels in grape roots and mature leaves. Further research demonstrated that the expression level of VhWRKY44 in grape roots and mature leaves was highly induced by salt and cold treatment. Compared with the control, Arabidopsis plants overexpressing VhWRKY44 showed stronger resistance to salt and cold stress. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased, and the contents of proline, malondialdehyde (MDA) and chlorophyll were changed considerably. In addition, significantly higher levels of stress-related genes were detected in the transgenic lines. The results indicated that VhWRKY44 was an important transcription factor in \'Beta\' with excellent salt and cold tolerance, providing a new foundation for abiotic stress research.

Metallothioneins (MTs) are non-enzymatic metal-binding proteins widely found in animals, plants, and microorganisms and are regulated by metal-responsive transcription factor 1 (MTF1). MT and MTF1 play crucial roles in detoxification, antioxidation, and anti-apoptosis. Therefore, they are key factors allowing organisms to endure the toxicity of heavy metal pollution. Phascolosoma esculenta is a marine invertebrate that inhabits intertidal zones and has a high tolerance to heavy metal stress. In this study, we cloned and identified MT and MTF1 genes from P. esculenta (designated as PeMT and PeMTF1). PeMT and PeMTF1 were widely expressed in all tissues and highly expressed in the intestine. When exposed to 16.8, 33.6, and 84 mg/L of zinc ions, the expression levels of PeMT and PeMTF1 in the intestine increased first and then decreased, peaking at 12 and 6 h, respectively, indicating that both PeMT and PeMTF1 rapidly responded to Zn stress. The recombinant pGEX-6p-1-MT protein enhanced the Zn tolerance of Escherichia coli and showed a dose-dependent ABTS free radical scavenging ability. After RNA interference (RNAi) with PeMT and 24 h of Zn stress, the oxidative stress indices (MDA content, SOD activity, and GSH content) and the apoptosis indices (Caspase 3, Caspase 8, and Caspase 9 activities) were significantly increased, implying that PeMT plays an important role in Zn detoxification, antioxidation, and anti-apoptosis. Moreover, the expression level of PeMT in the intestine was significantly decreased after RNAi with PeMTF1 and 24 h of Zn stress, which preliminarily proved that PeMTF1 has a regulatory effect on PeMT. Our data suggest that PeMT and PeMTF1 play important roles in the resistance of P. esculenta to Zn stress and are the key factors allowing P. esculenta to endure the toxicity of Zn.

LIM homeobox 4 (LHX4) is a transcription factor crucial for anterior pituitary (AP) development. Patients with LHX4 mutation suffer from combined pituitary hormone deficiency (CPHD), short statures, reproductive and metabolic disorders and lethality in some cases. Lhx4-knockout (KO) mice fail to develop a normal AP and die shortly after birth. Here, we characterize a zebrafish lhx4-KO model to further investigate the importance of LHX4 in pituitary gland development and regulation. At the embryonic and larval stages, these fish express lower levels of tshb mRNA compared with their wildtype siblings. In adult lhx4-KO fish, the expressions of pituitary hormone-encoding transcripts, including growth hormone (gh), thyroid stimulating hormone (tshb), proopiomelanocortin (pomca) and follicle stimulating hormone (fshb), are reduced, the pomca promoter-driven expression in corticotrophs is dampened and luteinizing hormone (lhb)-producing gonadotrophs are severely depleted. In contrast to Lhx4-KO mice, Lhx4-deficient fish survive to adulthood, but with a reduced body size. Importantly, lhx4-KO males reach sexual maturity and are reproductively competent, whereas the females remain infertile with undeveloped ovaries. These phenotypes, which are reminiscent of those observed in CPHD patients, along with the advantages of the zebrafish for developmental genetics research, make this lhx4-KO fish an ideal vertebrate model to study the outcomes of LHX4 mutation.

In response to biotic and abiotic stresses, the WRKY gene family plays a crucial role in plant growth and development. This study focused on Phoebe bournei and involved genome-wide identification of WRKY gene family members, clarification of their molecular evolutionary characteristics, and comprehensive mapping of their expression profiles under diverse abiotic stress conditions. A total of 60 WRKY gene family members were identified, and their phylogenetic classification revealed three distinct groups. A conserved motif analysis underscored the significant conservation of motif 1 and motif 2 among the majority of PbWRKY proteins, with proteins within the same class sharing analogous gene structures. Furthermore, an examination of cis-acting elements and protein interaction networks revealed several genes implicated in abiotic stress responses in P. bournei. Transcriptomic data were utilized to analyze the expression patterns of WRKY family members under drought and waterlogged conditions, with subsequent validation by quantitative real-time PCR (RT-qPCR) experiments. Notably, PbWRKY55 exhibited significant expression modulation under drought stress; PbWRKY36 responded prominently to waterlogging stress; and PbWRKY18, PbWRKY38, and PbWRKY57 demonstrated altered expression under both drought and waterlogging stresses. This study revealed the PbWRKY candidate genes that potentially play a pivotal role in enhancing abiotic stress resilience in P. bournei. The findings have provided valuable insights and knowledge that can guide further research aimed at understanding and addressing the impacts of abiotic stress within this species.

A novel MADS-box transcription factor from Pinus radiata D. Don was characterized. PrMADS11 encodes a protein of 165 amino acids for a MADS-box transcription factor belonging to group II, related to the MIKC protein structure. PrMADS11 was differentially expressed in the stems of pine trees in response to 45° inclination at early times (1 h). Arabidopsis thaliana was stably transformed with a 35S::PrMADS11 construct in an effort to identify the putative targets of PrMADS11. A massive transcriptome analysis revealed 947 differentially expressed genes: 498 genes were up-regulated, and 449 genes were down-regulated due to the over-expression of PrMADS11. The gene ontology analysis highlighted a cell wall remodeling function among the differentially expressed genes, suggesting the active participation of cell wall modification required during the response to vertical stem loss. In addition, the phenylpropanoid pathway was also indicated as a PrMADS11 target, displaying a marked increment in the expression of the genes driven to the biosynthesis of monolignols. The EMSA assays confirmed that PrMADS11 interacts with CArG-box sequences. This TF modulates the gene expression of several molecular pathways, including other TFs, as well as the genes involved in cell wall remodeling. The increment in the lignin content and the genes involved in cell wall dynamics could be an indication of the key role of PrMADS11 in the response to trunk inclination.

The toxic metal cadmium (Cd) poses a serious threat to plant growth and human health. Populus euphratica calcium-dependent protein kinase 21 (CPK21) has previously been shown to attenuate Cd toxicity by reducing Cd accumulation, enhancing antioxidant defense and improving water balance in transgenic Arabidopsis. Here, we confirmed a protein-protein interaction between PeCPK21 and Arabidopsis nuclear transcription factor YC3 (AtNF-YC3) by yeast two-hybrid and bimolecular fluorescence complementation assays. AtNF-YC3 was induced by Cd and strongly expressed in PeCPK21-overexpressed plants. Overexpression of AtNF-YC3 in Arabidopsis reduced the Cd inhibition of root length, fresh weight and membrane stability under Cd stress conditions (100 µM, 7 d), suggesting that AtNF-YC3 appears to contribute to the improvement of Cd stress tolerance. AtNF-YC3 improved Cd tolerance by limiting Cd uptake and accumulation, activating antioxidant enzymes and reducing hydrogen peroxide (H2O2) production under Cd stress. We conclude that PeCPK21 interacts with AtNF-YC3 to limit Cd accumulation and enhance the reactive oxygen species (ROS) scavenging system and thereby positively regulate plant adaptation to Cd environments. This study highlights the interaction between PeCPK21 and AtNF-YC3 under Cd stress conditions, which can be utilized to improve Cd tolerance in higher plants.