Biology subjects

Mani, B.

Publications and source records attributed to Mani, B..

3 recordsLinked to original sources

bioRxiv2025

The EXS domain of rice PHOSPHATE1 (OsPHO1;2) reduces the low phosphate response through jasmonate signaling

Phosphorus (P) is a vital macronutrient essential for plant growth, and its deficiency significantly hampers agricultural productivity. The PHOSPHATE 1 (PHO1) protein family, characterized by an N-terminal SPX domain, four transmembrane (4TM) domains, and a C-terminal EXS domain, is pivotal in transporting phosphate (Pi) from roots to shoots. Rice, PHO1;2 plays a crucial role in the Pi export process, and defects in this gene cause severe growth retardation and Pi deficiency symptoms even when external Pi levels are adequate. This study examined the roles of the EXS domain and the combined 4TM+EXS domains of OsPHO1;2 in supporting plant growth responses, independent of Pi transport activity, as well as their influence on hormone signaling and gene regulation. Using CRISPR/Cas9, rice lines expressing specific OsPHO1;2 domains (EXS or 4TM+EXS) were created by targeted deletion of particular domain-coding regions. Phenotypic analysis under Pi-sufficient and deficient conditions, as well as phosphate profiling, revealed that EXS lines exhibited notably better growth than loss-of-function mutants, ospho1;2, during early development, despite having similar shoot Pi levels to the null mutant. These lines showed lower levels of defense hormones (jasmonic acid) than ospho1;2 but were comparable to those in the wild type. Conversely, 4TM+EXS lines exhibited growth patterns similar to ospho1;2 mutants. RNA sequencing indicated that the phosphate starvation response (PSR) and defense pathways were less pronounced in the EXS lines compared to ospho1;2 mutants. However, both EXS and 4TM+EXS lines showed seed development defects and reduced total phosphorus content in seeds, mirroring the ospho1;2 phenotype. Heterozygous plants carrying one functional OsPHO1;2 allele displayed normal growth and seed development, indicating the mutations recessive nature. The findings suggest that the EXS domain of OsPHO1;2 can promote plant growth independently of Pi transport by decreasing PSR and modulating defense hormone pathways. This further suggests a signaling role for PHO1 domains beyond direct Pi translocation. Overall, these results enhance our understanding of Pi homeostasis and may help form strategies for breeding P-efficient crops.

molecular biology↗

bioRxiv2024

Editing cis-elements of OsPHO1;2 improved phosphate transport and yield in rice

Increasing grain yield is the main aim of crop improvement, which is globally impacted by the low availability of soil phosphate (Pi). Overexpressing Pi transporters for increasing Pi uptake often result in Pi toxicity and growth retardation. Despite advancements in genetic engineering, targeting cis-regulatory motifs of Pi transporters remains underexplored for understanding plant mechanisms and improving Pi status. Here, we demonstrated that the excision of the transcription inhibitor motif from the promoter of Pi transporter, OsPHO1;2, enhanced its expression and increased root-to-shoot Pi transport, leading to improved grain yield. Using, in-silico and DNA-protein interaction studies, we show the role of OsWRKY6 transcription factor in the negative regulation of OsPHO1;2 expression by binding to the cis-regulatory element (W-box) present in its promoter. oswrky6 knockout lines displayed a higher OsPHO1;2 expressions, and improved shoot Pi levels. Further, we engineered the OsPHO1;2 promoter for precisely removing the W-box and enhancing OsPHO1;2 expression. The phenotypic and physiological evaluation at the vegetative stage shows that OsPHO1;2 promoter edited (OsPHO1;2:PE) lines have increased shoot length, plant biomass and more root-shoot Pi export under low and normal P conditions. Notably, the 33Pi uptake assay reveals that OsPHO1;2:PE lines exhibited enhanced root Pi uptake, supported by higher root-associated Pi transporters (OsPHTs) expression. An extensive agronomical assessment revealed that OsPHO1;2:PE lines acquire increased seed and panicle numbers, thereby increasing yield without affecting seed quality. Our findings offer valuable insight into the potential of promoter editing to raise plants with better Pi use and improved crop yield.

plant biology↗

bioRxiv2018

Relative Reduction of the Biological and phylogenetic diversity of oral microbiome in diabetic and pre-diabetic subjects

BackgroundThere is a suggested reciprocal relationship between oral health and systemic disease such as type 2 diabetes. In this relationship, a systemic disease predisposing to oral infection, and when that infection is present, the oral infection aggravates the progression of the systemic disease. Several studies suggested that some oral microbiome constituents are linked to both diabetes, metabolic syndrome and obesity. This study aims to compare the microbial diversity and population structure of oral microbiome among normoglycemic, impaired glucose tolerance (IGT) and diabetic subjects.\n\nMethodologyThis study followed a case-control design (15 T2D patients, 10 IGTs and, 19 controls). Patient records were screened as per the inclusion and exclusion criteria. Assessment of periodontitis and oral health was performed to all subjects. DNA Isolation purification and quantification from collected Saliva samples were performed. 16SrRNA hypervariable regions were amplified and sequenced. Generated sequences were subjected to bioinformatics analysis. Statistical analysis and diversity indices were computed with the statistical software R, the vegan R-package, and Past318 software.\n\nResultsA total observed number of 551 OTUs. A clear reduction of the number of species (OTUs) was observed in both IGT (412) and diabetic group (372) compared with the normoglycemic group (502). This was associated with a similar pattern of biological diversity among the three groups. Phylogenetic diversity (PD-SBL) value in the normoglycemic group was higher than the diabetic group. The diabetic group had the highest evenness value and the highest microbiome bacterial pathogenic content.\n\nConclusionWe observed a clear reduction in the biological and phylogenetic diversity in the diabetic and pre-diabetic oral microbiome in comparison with the normoglycemic oral microbiome. However, this reduction was associated with an increase in the pathogenic content of the hyperglycemic microbiomes.

microbiology↗