Publications of NIPGR Scientists
Permanent URI for this communityhttps://ndkr-library.nipgr.ac.in/handle/123456789/1
Browse
4 results
Search Results
Item OsMED14_2, a tail module subunit of mediator complex, controls rice development and involves jasmonic acid(Elsevier B.V., 2024) Prusty, Ankita; Mehra, Poonam; Sharma, Shivam; Malik, Naveen; Agarwal, Pinky; Parida, Swarup K.; Kapoor, Sanjay; Tyagi, Akhilesh K.The Mediator complex is essential for eukaryotic transcription, yet its role and the function of its individual subunits in plants, especially in rice, remain poorly understood. Here, we investigate the function of OsMED14_2, a subunit of the Mediator tail module, in rice development. Overexpression and knockout of OsMED14_2 resulted in notable changes in panicle morphology and grain size. Microscopic analysis revealed impact of overexpression on pollen maturation, reflected by reduced viability, irregular shapes, and aberrant intine development. OsMED14_2 was found to interact with proteins involved in pollen development, namely, OsMADS62, OsMADS63 and OsMADS68, and its overexpression negatively affected the expression of OsMADS68 and the expression of other genes involved in intine development, including OsCAP1, OsGCD1, OsRIP1, and OsCPK29. Additionally, we found that OsMED14_2 overexpression influences jasmonic acid (JA) homeostasis, affecting bioactive JA levels, and expression of OsJAZ genes. Our data suggest OsMED14_2 may act as a regulator of JA-responsive genes through its interactions with OsHDAC6 and OsJAZ repressors. These findings contribute to better understanding of the Mediator complex's role in plant traits regulation.Item Mediator subunit OsMED14_1 plays an important role in rice development(John Wiley & Sons, 2020) Malik, Naveen; Ranjan, Rajeev; Parida, Swarup K.; Agarwal, Pinky; Tyagi, Akhilesh K.Mediator, a multi‐subunit coactivator complex, regulates transcription in eukaryotes and is involved in diverse processes in Arabidopsis through its different subunits. Here, we have explored developmental aspects of one of the rice Mediator subunit gene OsMED14_1. We analyzed its expression pattern through RNA in‐situ hybridization and pOsMED14_1:GUS transgenics which showed its expression in roots, leaves, anthers and seeds prominently at younger stages, indicating possible involvement of this subunit in multiple aspects of rice development. To understand developmental roles of OsMED14_1 in rice, we generated and studied RNAi based knockdown rice plants which showed multiple effects including less height, narrower leaves and culms with reduced vasculature, lesser lateral root branching, defective microspore development, reduced panicle branching and seed set, and smaller seeds. Histological analyses showed that slender organs were caused by reduction in both cell number and cell size in OsMED14_1 knockdown plants. Flow cytometric analyses and expression analyses of cell‐cycle related genes revealed that defective cell‐cycle progression led to these defects. Expression analyses of auxin related genes and IAA immuno‐localization study indicated altered auxin level in these knockdown plants. Reduction of lateral root branching in knockdown plants was corrected by exogenous IAA supplement. OsMED14_1 physically interacts with transcription factors YABBY5, TDR and MADS29, possibly regulating auxin homeostasis and ultimately leading to lateral organ/leaf, microspore and seed development.Item Genome-wide expressional and functional analysis of calcium transport elements during abiotic stress and development in rice(John Wiley & Sons, 2014) Singh, Amarjeet; Kanwar, Poonam; Yadav, Akhilesh K.; Mishra, Manali; Jha, Saroj K.; Baranwal, Vinay; Pandey, Amita; Kapoor, Sanjay; Tyagi, Akhilesh K.; Pandey, Girdhar K.Ca²⁺ homeostasis is required to maintain a delicate balance of cytosolic Ca²⁺ during normal and adverse growth conditions. Various Ca²⁺ transporters actively participate to maintain this delicate balance especially during abiotic stresses and developmental events in plants. In this study, we present a genome-wide account, detailing expression profiles, subcellular localization and functional analysis of rice Ca²⁺ transport elements. Exhaustive in silico data mining and analysis resulted in the identification of 81 Ca²⁺ transport element genes, which belong to various groups such as Ca²⁺-ATPases (pumps), exchangers, channels, glutamate receptor homologs and annexins. Phylogenetic analysis revealed that different Ca²⁺ transporters are evolutionarily conserved across different plant species. Comprehensive expression analysis by gene chip microarray and quantitative RT-PCR revealed that a substantial proportion of Ca²⁺ transporter genes were expressed differentially under abiotic stresses (salt, cold and drought) and reproductive developmental stages (panicle and seed) in rice. These findings suggest a possible role of rice Ca²⁺ transporters in abiotic stress and development triggered signaling pathways. Subcellular localization of Ca²⁺ transporters from different groups in Nicotiana benthamiana revealed their variable localization to different compartments, which could be their possible sites of action. Complementation of Ca²⁺ transport activity of K616 yeast mutant by Ca²⁺-ATPase OsACA7 and involvement in salt tolerance verified its functional behavior. This study will encourage detailed characterization of potential candidate Ca²⁺ transporters for their functional role in planta.Item Comprehensive expression analysis of rice Armadillo gene family during abiotic stress and development(Oxford University Press, 2014) Sharma, Manisha; Singh, Amarjeet; Shankar, Alka; Pandey, Amita; Baranwal, Vinay; Kapoor, Sanjay; Tyagi, Akhilesh K.; Pandey, Girdhar K.Genes in the Armadillo (ARM)-repeat superfamily encode proteins with a range of developmental and physiological processes in unicellular and multicellular eukaryotes. These 42 amino acid, long tandem repeat-containing proteins have been abundantly recognized in many plant species. Previous studies have confirmed that Armadillo proteins constitute a multigene family in Arabidopsis. In this study, we performed a computational analysis in the rice genome (Oryza sativa L. subsp. japonica), and identified 158 genes of Armadillo superfamily. Phylogenetic study classified them into several arbitrary groups based on a varying number of non-conserved ARM repeats and accessory domain(s) associated with them. An in-depth analysis of gene expression through microarray and Q-PCR revealed a number of ARM proteins expressing differentially in abiotic stresses and developmental conditions, suggesting a potential roles of this superfamily in development and stress signalling. Comparative phylogenetic analysis between Arabidopsis and rice Armadillo genes revealed a high degree of evolutionary conservation between the orthologues in two plant species. The non-synonymous and synonymous substitutions per site ratios (Ka/Ks) of duplicated gene pairs indicate a purifying selection. This genome-wide identification and expression analysis provides a basis for further functional analysis of Armadillo genes under abiotic stress and reproductive developmental condition in the plant lineage.