Abstract
BackgroundIntracellular Na+ (K+)/H+ antiporters (NHXs) have pivotal functions in regulating plant growth, development, and resistance to a range of stresses. To gain insight into the molecular events underlying their actions in switchgrass (Panicum virgatum L.), we analyzed transcriptomic changes between PvNHX1-overexpression transgenic lines and wild-type (WT) plants using RNA sequencing (RNA-seq) technology.ResultsThe comparison of transcriptomic data from the WT and transgenic plants revealed a large number of differentially expressed genes (DEGs) in the latter. Gene ontology (GO) and KEGG pathway analyses showed that these DEGs were associated with a wide range of functions, and participated in many biological processes. For example, we found that PvNHX1 had an important role in plant growth through its regulation of photosynthetic activity and cell expansion. In addition, PvNHX1 regulated K+ homeostasis, cell expansion and pollen development, indicating that it has unique and specific roles in flower development. We also found that transgenic switchgrass exhibited a higher level of transcription of defense-related genes, especially those involved in disease resistance.ConclusionWe showed that PvNHX1 had an important role in plant growth and development through its regulation of photosynthetic activity, cell expansion, K+ homeostasis, and pollen development. Additionally, PvNHX1 overexpression activated a complex signal transduction network in response to various biotic and abiotic stresses. In relation to plant growth, development, and defense responses, PvNHX1 also had a vital regulatory role in the formation of a series of plant hormones and transcription factors (TFs). The reliability of the RNA-seq data was confirmed by quantitative real-time PCR. Our data provide a valuable foundation for further research into the molecular mechanisms and physiological roles of NHXs in plants.
Highlights
Intracellular Na+ (K+)/H+ antiporters (NHXs) have pivotal functions in regulating plant growth, development, and resistance to a range of stresses
Switchgrass callus generated from mature seeds was transformed with a Ubi1301 binary vector harboring a PvNHX1 overexpression cassette using the Agrobacterium-mediated transformation method described previously [16]
When the plants reached the reproductive 1 (R1) stage [17], the mature leaves of internode 3 (I3) from six independent plants were pooled for RNA extraction and frozen in liquid nitrogen for later quantitative real-time PCR (qRT-PCR) analysis
Summary
Intracellular Na+ (K+)/H+ antiporters (NHXs) have pivotal functions in regulating plant growth, development, and resistance to a range of stresses. To gain insight into the molecular events underlying their actions in switchgrass (Panicum virgatum L.), we analyzed transcriptomic changes between PvNHX1overexpression transgenic lines and wild-type (WT) plants using RNA sequencing (RNA-seq) technology. Novel functions of NHXtype Na+/H+ antiporters were identified, including roles in cell expansion, cell volume regulation, flower development, stomatal conductance, protein processing, and vesicular trafficking [8,9,10]. RNA-seq technology is a powerful method to analyze the expression of genes at the transcriptome level and will provide a better understanding of the mechanisms underlying NHX function
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
