Jul 2026· Journal of Advanced Research· 0 citations· 67 references
Medicine
TL;DR
The uncharacterized gene, GhFIR_A08 is revealed to positively regulate fiber initiation to increase LP, and provides valuable genetic resources for molecular breeding aimed at improving cotton yield.
Abstract
INTRODUCTION
Cotton is an important global economic crop, and enhancing yield remains a primary breeding objective. Fiber development is controlled by a complex regulatory network, with the initiation stage being pivotal because it determines fiber number and ultimately yield. However, most studies have focused on upstream transcription factors, leaving downstream functional genes largely uncharacterized.
Objectives
To explore the gene function and regulatory network of the unannotated gene GhFIR_A08 (Fiber Initiation Regulator on chromosome A08), which was identified based on previous structural-variant analyses and highly expressed during fiber initiation.
Methods
Currently high-quality Gossypium genome assemblies were compared to investigate the origin of the FIRs gene family and the mechanism of transposon-mediated copy number variation. Gene function was evaluated by generating stable homozygous transgenic lines (both knockout and overexpression) in the recipient backgrounds. Interacting proteins were screened and verified by MBP pull-down combined with mass spectrometry, yeast two-hybrid, bimolecular fluorescence complementation, and pull-down assays. The regulatory network was explored by yeast one-hybrid, dual-luciferase reporter, electrophoretic mobility shift assays, RNA-seq, and measurements of related metabolites.
Results
Alongside the evolutionary origin and polyploidization-driven expansion of this gene family in Gossypium, a transposon-mediated, haplotype-specific loss of GhFIR_A08 was uncovered. Overexpressing GhFIR_A08 increased the number of ovule protrusions and enhanced lint percentage (LP), whereas knockout produced the opposite phenotype. An upstream regulatory hierarchy was further uncovered in which GhWRKY16 induces another activator, GhRL6; both GhWRKY16 and GhRL6 bind the respective sites of GhFIR_A08 promoter, forming a coherent GhWRKY16-GhRL6-GhFIR_A08 module to activate GhFIR_A08. Functionally, GhFIR_A08 cooperates with Gh14-3-3, GhHSP70, GhSPL13, and GhPPR to regulate cotton fiber initiation by modulating hormone signaling, protein homeostasis, and redox processes.
Conclusion
The uncharacterized gene, GhFIR_A08 is revealed to positively regulate fiber initiation to increase LP, and provides valuable genetic resources for molecular breeding aimed at improving cotton yield.
Begonia semperflorens is an important ornamental plant worldwide, but its practical application is severely limited by low temperature sensitivity. However, the molecular regulatory mechanisms underlying low temperature-induced anthocyanin biosynthesis remain unclear. In this study, we assembled a high-quality chromosome-level B. semperflorens genome. Through genomic and MYB gene family analysis, we identified a key transcription factor BsTT2, which directly binds to the BsDFR promoter and enhances its activity, thereby driving anthocyanin accumulation in B. semperflorens. Furthermore, using BsTT2 as bait, we identified its interacting protein BsAlfin2. Under low temperature-induced reactive oxygen species (ROS) signaling, BsAlfin2 undergoes nuclear translocation and forms a complex with BsTT2, synergistically enhancing the activation of the BsDFR promoter and significantly improving anthocyanin production efficiency. Based on these results, we propose a previously uncharacterized BsAlfin2/BsTT2-BsDFR regulatory module, which reveals a molecular links low-temperature ROS signaling to anthocyanin biosynthesis in B. semperflorens. In summary, this study not only provides chromosome-level genomic resources for B. semperflorens research but also elucidates a key molecular module in low temperature-induced anthocyanin biosynthesis regulatory pathway, laying a theoretical and data foundation for future studies on leaf color improvement and stress resistance breeding in Begonia.
Introduction Alternative oxidase (AOX) is a core functional protein that mitigates excessive mitochondrial reactive oxygen species (ROS) accumulation and modulates plant stress adaptation, and its biological activity is tightly controlled by sophisticated regulatory networks.The cotton cytoplasmic male sterile (CMS) line Jin A represents an optimal model for dissecting the functional characteristics of GhAOX genes, as it exhibits pronounced ROS overaccumulation and aberrant GhAOX transcriptional profiles in anthers during the critical developmental stage of pollen mother cell degeneration, relative to its maintainer Jin B. Methods We conducted a genome-wide identification of the GhAOX gene family in upland cotton (Gossypium hirsutum) and systematically characterized the molecular features of GhAOX members in Jin A at the transcriptional, translational, post-translational modification, and gene structural levels. Results A total of eight GhAOX genes were identified, among which GhAOX2b1/2 and GhAOX2c1/2 displayed anther-preferential expression patterns and were significantly upregulated in response to multiple abiotic stresses, including osmotic stress (PEG), salinity (NaCl), cold (4℃) and heat (37℃). Functional validation via overexpression and virus-induced gene silencing (VIGS) assays verified the ROS-scavenging capacity of GhAOX. Notably, in Jin A, despite elevated GhAOX protein abundance, its enzymatic activity was substantially compromised, which was attributed to perturbed transcriptional regulation, isoform-specific differential activation by tricarboxylic acid (TCA) cycle intermediates, and reduced abundance of mitochondrial effector molecules. Discussion This dysregulation was likely implicated in the aberrant ROS accumulation underlying the pollen abortion phenotype in Jin A. Collectively, this study establishes a comprehensive molecular framework for elucidating the multi-level regulatory mechanisms of AOX in response to intracellular microenvironmental perturbations and uncovers its pivotal role in regulating reproductive fitness in upland cotton.
Jinlong Zhang, Li Zhang, Yuekai Su et al.· Frontiers in Plant Science· 0 citations
Findings establish BrBGLU10 as an important regulator of pollen development and a potential target for fertility-related applications via gene editing in B. rapa and related Brassica crops.
Ying Huang, Shanxin Zhong, Tian-Ci Hu et al.· Plants· 0 citations
Drought stress is a major abiotic factor limiting cotton yield and quality. RING-type E3 ubiquitin ligases play central regulatory roles in plant stress responses; however, the functions and regulatory networks of this gene family in cotton drought response remain largely unclear. In this study, we characterized the RING-type E3 ubiquitin ligase gene GhRNG1L from upland cotton (Gossypium hirsutum L.) and demonstrated its role in enhancing drought tolerance in cotton, and we successfully identified its upstream transcription factor GhDREB2B. Functional assays showed that overexpression of GhRNG1L significantly increased catalase (CAT) activity and reduced hydrogen peroxide (H2O2) accumulation in Arabidopsis, thereby improving plant drought tolerance, whereas silencing GhRNG1L produced the opposite phenotype. Further molecular analysis confirmed that GhDREB2B directly binds to the promoter of GhRNG1L and activates its transcription. Collectively, our findings reveal, for the first time, the positive regulatory role of the GhDREB2B-GhRNG1L module in cotton drought response, providing a clear upstream regulatory target and theoretical basis for molecular breeding of drought-tolerant cotton.
Meng-Yan Wang, Li An, Xiao-Kang Fu et al.· Plants· 0 citations
Leafy head formation is a critical agronomic trait that determines the yield and quality of Chinese cabbage (Brassica rapa), involving complex morphological transitions. While BEL1-like homeodomain (BLH) transcription factors regulate development, their specific roles in heading remain elusive. To systematically identify the BraBLH gene family and elucidate its expression networks and regulatory functions during leafy head formation, a total of 36 BraBLH genes were identified. The phylogenetic analysis revealed that Brassica rapa had a specific clade (Group II). A high-resolution spatiotemporal expression framework for the BraBLH family was constructed. Subsequently, comparative transcriptomics of heading, non-heading, and GA3-treated heading plants highlighted multiple differentially expressed BraBLH genes, suggesting that this gene family may contribute to the regulation of leafy head formation in Chinese cabbage. Subsequently, a high-resolution spatiotemporal expression framework for the BraBLH family was constructed. Within this framework, BraBLH5 emerged as a pivotal node integrating GA signaling, peaking during the rosette stage to initiate heading. In contrast, a distinct negative module (BraBLH9/26) was significantly upregulated in the non-heading line. Spatial profiling further revealed functional compartmentalization within the family, where specific members maintained shoot apical meristem identity, whereas others drove inner leaf expansion and incurvature. Furthermore, subcellular localization analysis confirmed that BraBLH5 was localized to the nucleus. Ultimately, this systems-level study elucidates a transcriptome-driven framework for heading, highlighting a GA-mediated BraBLH5 mechanism and providing valuable candidates for Brassica functional genomics.