Project description:Post-transcriptional gene regulation plays a significant role in the response to Pi starvation. Here, we utilized advances in next-generation sequencing technology to examine changes in transcriptional control, RNA association with translating ribosomes in 14-day-old Arabidopsis seedlings subjected to 7 days of Pi starvation.
Project description:We performed a transcriptomic analysis of Pi starvation responses in Arabidopsis thaliana (Columbia-0) wild type plants under phosphate starvation stress and in plants with altered PHR1(-like) activity, comparing mutants of phr1 and phr1-phl1 grown in phosphate-lacking medium. Results show the central role of PHR1 and functionally redundant members of its family in the control of transcriptional responses to Pi starvation.
Project description:We report global gene expression profilies of Brassinosteroid related Arabidopsis mutants in response to dehydration and fixed-carbon starvation stresses by RNA-seq
Project description:Plants possess an enormous plasticity to adapt their metabolism to the fluctuating energy supply in a natural environment. Using dark-induced senescence (DIS) as an experimental system, a mutant study combining phenotypical, transcriptomic and Chromatin Immunoprecipitation Sequencing (ChIPseq) approaches identifies distinct members of the Arabidopsis group S1 basic leucine zipper transcription factors that orchestrate the starvation response. While excluding bZIP2, bZIP11 and bZIP44 to function in DIS, the in part redundantly acting bZIP1 and bZIP53 control a co-expression network governing amino acid catabolism and transport, gluconeogenesis and energy homeostasis. Moreover, they regulate genes involved in asparagine – glutamine balance, which are critical for C/N homeostasis. This transcriptional reprogramming in resource management is required for survival during starvation and regaining meristematic activity during recovery from stress. Thus, we provide insights into the transcriptional control of plant resource and energy management during starvation. Finally, this work sheds light on the discrepancy between in vitro DNA-binding and overexpression studies versus mutant analyses and in vivo DNA-binding, providing a critical view on how to define specific transcription factor functions within large families.
Project description:We investigated eisosome rearrangement during glucose starvation. Pil1 phosphorylation was assessed in control and starvation conditions.
Project description:We performed a transcriptomic analysis of Pi starvation responses in Arabidopsis thaliana (Columbia-0) phr1 mutant plants expressing PHR1 in presence of cicloheximide, that inhibit protein translation, thus preventing any effect of PHR1 on the expression of indirect targets. Results show the primary target genes of PHR1 in the responses to Pi starvation.
Project description:Renal gluconeogenesis accounts for a substantial fraction of systemic glucose production during starvation, yet its regulation and pathological disruption in chronic kidney disease (CKD) remain poorly understood. Here, we investigated the mechanisms governing renal gluconeogenesis during starvation and their impairment in CKD. Integrated transcriptome analysis of starved mouse kidneys revealed that starvation robustly induces gluconeogenic gene expression in proximal tubular epithelial cells through activation of FOXO1. Consistently, tubule-specific deletion of FOXO1 (FOXO1^flox/flox^; Ksp-Cre) markedly reduced renal gluconeogenic enzyme expression and resulted in hypoglycemia during starvation, establishing FOXO1 as a critical regulator of renal glucose production. In multiple CKD models, basal serum glucose levels were preserved despite suppressed renal FOXO1 activation and gluconeogenic gene expression, indicating compensatory glucose production under fed conditions. In contrast, during prolonged starvation, CKD mice developed profound hypoglycemia accompanied by impaired FOXO1 activation and insufficient induction of renal gluconeogenesis, a phenotype that was similarly observed in aged mice. In human CKD kidneys, a senescent tubular cell state was associated with coordinated downregulation of gluconeogenesis-related genes. These findings were recapitulated in cisplatin-induced senescence models, which showed diminished FOXO1 activity, reduced gluconeogenic gene expression, and decreased glucose production. Collectively, these findings identify tubular cell senescence as a pathogenic mechanism that disrupts FOXO1-dependent renal gluconeogenesis, thereby compromising glucose homeostasis during starvation in CKD and aging. Targeting tubular senescence or restoring FOXO1 signaling may represent therapeutic strategies to prevent starvation-induced hypoglycemia in these conditions.
Project description:This SuperSeries is composed of the following subset Series: GSE33790: The response and recovery of Arabidopsis thaliana transcriptome to phosphate starvation [ATH1-121501] GSE33996: The response and recovery of Arabidopsis thaliana transcriptome to phosphate starvation [At35b_MR] Refer to individual Series