School Of Basic And Applied Sciences
Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/17
Browse
2 results
Search Results
Item Studies on adaptive environmental responses in Himalayan Rhododendron arboreum(Central University of Punjab, 2019) Choudhary, Shruti; Bhardwaj, PankajTemperate plants acclimatize to survive freezing temperatures, which are otherwise prerequisite in the initiation/transition of a developmental phase. The dominance of Rhododendron arboreum under a highly fluctuating Himalayan environment makes it enticing for genetic structure and functional analysis. In the present study, transcript, small RNA and metabolome libraries from flowers and foliar tissues of reproductive and vegetative seasons were analyzed. The high-quality paired-end reads were assembled into 157,427 non-redundant transcripts and categorized functionally based on gene ontology, pathway, and transcription factor database. The screening for molecular markers identified 35,419 SSR and 811 high-quality SNPs. A comparison of transcript profiles for the vegetative and flowering season tissues revealed that 12,577 unigenes with fluctuating expression were responsible for seasonal adaptations. Additional to the gene interaction networks, 421 ions obtained from LC-MS were annotated to distinct pathways, especially secondary metabolites. Thirdly, 466 conserved and novel miRNAs, 442 precursors, and 27,139 targets were predicted and the miRNAs modulating circadian clock and reproductive development were discussed further. Other than the genes, miRNAs, and compounds held for an active metabolism, signaling, development, and their regulations, supplementary responses to abiotic/biotic stimuli were induced. A multifaceted response not only sponsored the climatic encounters but brought the shift from vegetative to reproductive growth. The genome-wide profiling and the spatiotemporal variation in mRNA and miRNA expression, as well as the nontargeted metabolome, will enhance the understanding of development and tolerance strategies in high altitude tree species.Item Exploring microRNA profiles for circadian clock and flowering development regulation in Himalayan Rhododendron(Elsevier, 2018) Choudhary, Shruti; Thakur, Sapna; Majeed, Aasim; Bhardwaj, PankajmiRNA is a non-coding, yet crucial entity in remodeling the genetic architecture. Rhododendron arboreum of Himalayas grows and even flower under fluctuating climate. sRNA from leaves of vegetative and reproductive periods was sequenced to elucidate its seasonal associations. Conserved (256) and novel (210) miRNAs and their precursors were located based on homology with plant databases and transcriptome of the species. 27,139 predicted targets were involved with metabolism, reproduction, and response to abiotic stimuli. A comparative analysis showed differential expression of 198 miRNAs with season-specific abundance of 103 miRNAs. Specific isoforms of 11 miRNA families exhibited a temporal expression and targeted different genes implying a complex regulation. The variable miRNA expression among the tissues of different conditions can be associated with the adaptability of the species, which will prove essential for further study on miRNAs mediating seasonal response. Moreover, exogenous cues also mediate phase transition via networking of flowering pathways and their components. In this context, 18 known families and 77 novel miRNAs modulating 117 genes crucial in circadian entrainment were filtered. A negative correlation was obtained between the expression of 18 of these miRNAs and their targets when tested through quantitative-PCR. It highlighted the role of miRNA-target pairs in perceiving environmental variabilities and monitoring flowering growth. Furthermore, a phylogenetic clustering was performed, which supported the lineage-specific evolution and function of putative miR156 sequence in the species. This documentation of genome-wide profiling of miRNA, their targets, and expression will enhance the understanding of developmental and climate-tolerance strategies in high-altitude trees.