Acute hypoxia elevates arginase 2 and induces polyamine stress response in zebrafish via evolutionarily conserved mechanism

AbstractExpression of stress response genes can be regulated by abscisic acid (ABA) dependent and ABA independent pathways. Osmotic stresses promote ABA accumulation, therefore inducing the expression of stress response genes via ABA signaling. Whereas cold and heat stresses induce the expression of stress response genes via ABA independent pathway. ABA induced transcription repressors (AITRs) are a family of novel transcription factors that play a role in ABA signaling, and Drought response gene (DRG) has previously been shown to play a role in regulating plant response to drought and freezing stresses. We report here the identification of DRG as a novel transcription factor and a regulator of ABA response in Arabidopsis. We found that the expression of DRG was induced by ABA treatment. Homologs searching identified AITR5 as the most closely related Arabidopsis protein to DRG, and homologs of DRG, including the AITR-like (AITRL) proteins in bryophytes and gymnosperms, are specifically presented in embryophytes. Therefore we renamed DRG as AITRL. Protoplast transfection assays show that AITRL functioned as a transcription repressor. In seed germination and seedling greening assays, the aitrl mutants showed an increased sensitivity to ABA. By using qRT-PCR, we show that ABA responses of some ABA signaling component genes including some PYR1-likes (PYLs), PROTEIN PHOSPHATASE 2Cs (PP2Cs) and SUCROSE NONFERMENTING 1 (SNF1)-RELATED PROTEIN KINASES 2s (SnRK2s) were reduced in the aitrl mutants. Taken together, our results suggest that AITRLs are a family of novel transcription repressors evolutionally conserved in embryophytes, and AITRL regulates ABA response in Arabidopsis by affecting ABA response of some ABA signaling component genes.

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C. elegans discriminates colors to guide foraging

Science ◽

10.1126/science.abd3010 ◽

2021 ◽

Vol 371 (6533) ◽

pp. 1059-1063 ◽

Cited By ~ 1

Author(s):

D. Dipon Ghosh ◽

Dongyeop Lee ◽

Xin Jin ◽

H. Robert Horvitz ◽

Michael N. Nitabach

Keyword(s):

Stress Response ◽

Cellular Stress ◽

Color Discrimination ◽

Cellular Stress Response ◽

Blue Pigment ◽

Natural Environments ◽

C Elegans ◽

Evolutionarily Conserved ◽

Foraging Decisions ◽

Light Guides

Color detection is used by animals of diverse phyla to navigate colorful natural environments and is thought to require evolutionarily conserved opsin photoreceptor genes. We report that Caenorhabditis elegans roundworms can discriminate between colors despite the fact that they lack eyes and opsins. Specifically, we found that white light guides C. elegans foraging decisions away from a blue-pigment toxin secreted by harmful bacteria. These foraging decisions are guided by specific blue-to-amber ratios of light. The color specificity of color-dependent foraging varies notably among wild C. elegans strains, which indicates that color discrimination is ecologically important. We identified two evolutionarily conserved cellular stress response genes required for opsin-independent, color-dependent foraging by C. elegans, and we speculate that cellular stress response pathways can mediate spectral discrimination by photosensitive cells and organisms—even by those lacking opsins.

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Crucial Players for Inter-Organelle Communication: PI5P4Ks and Their Lipid Product PI-4,5-P2 Come to the Surface

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.791758 ◽

2022 ◽

Vol 9 ◽

Author(s):

Archna Ravi ◽

Lavinia Palamiuc ◽

Brooke M. Emerling

Keyword(s):

Stress Response ◽

Human Diseases ◽

Type Ii ◽

Metabolic Homeostasis ◽

Cellular Homeostasis ◽

Evolutionarily Conserved ◽

Lipid Product ◽

Canonical Type ◽

Organelle Communication ◽

A Minor

While organelles are individual compartments with specialized functions, it is becoming clear that organellar communication is essential for maintaining cellular homeostasis. This cooperation is carried out by various interactions taking place on the membranes of organelles. The membranes themselves contain a multitude of proteins and lipids that mediate these connections and one such class of molecules facilitating these relations are the phospholipids. There are several phospholipids, but the focus of this perspective is on a minor group called the phosphoinositides and specifically, phosphatidylinositol 4,5-bisphosphate (PI-4,5-P2). This phosphoinositide, on intracellular membranes, is largely generated by the non-canonical Type II PIPKs, namely, Phosphotidylinositol-5-phosphate-4-kinases (PI5P4Ks). These evolutionarily conserved enzymes are emerging as key stress response players in cells. Further, PI5P4Ks have been shown to modulate pathways by regulating organelle crosstalk, revealing roles in preserving metabolic homeostasis. Here we will attempt to summarize the functions of the PI5P4Ks and their product PI-4,5-P2 in facilitating inter-organelle communication and how they impact cellular health as well as their relevance to human diseases.

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SLR-2 and JMJC-1 regulate an evolutionarily conserved stress-response network

The EMBO Journal ◽

10.1038/emboj.2009.387 ◽

2010 ◽

Vol 29 (4) ◽

pp. 727-739 ◽

Cited By ~ 20

Author(s):

Natalia V Kirienko ◽

David S Fay

Keyword(s):

Stress Response ◽

Response Network ◽

Evolutionarily Conserved

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Adrenocorticotropic hormone and corticosterone responses to acute hypoxia in the neonatal rat: effects of body temperature maintenance

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00708.2010 ◽

2011 ◽

Vol 300 (3) ◽

pp. R708-R715 ◽

Cited By ~ 18

Author(s):

Eric D. Bruder ◽

Kimberli J. Kamer ◽

Mitchell A. Guenther ◽

Hershel Raff

Keyword(s):

Stress Response ◽

Body Temperature ◽

Acute Hypoxia ◽

Plasma Corticosterone ◽

Neonatal Rat ◽

Plasma Acth ◽

Neonatal Hypoxia ◽

Rat Pups ◽

Expression Of Genes ◽

Corticosterone Response

The corticosterone response to acute hypoxia in neonatal rats develops in the 1st wk of life, with a shift from ACTH independence to ACTH dependence. Acute hypoxia also leads to hypothermia, which may be protective. There is little information about the endocrine effects of body temperature maintenance during periods of neonatal hypoxia. We hypothesized that prevention of hypothermia during neonatal hypoxia would augment the adrenocortical stress response. Rat pups separated from their dams were studied at postnatal days 2 and 8 ( PD2 and PD8). In one group of pups, body temperature was allowed to spontaneously decrease during a 30-min prehypoxia period. Pups were then exposed to 8% O2 for 3 h and allowed to become spontaneously hypothermic or externally warmed (via servo-controlled heat) to maintain isothermia. In another group, external warming was used to maintain isothermia during the prehypoxia period, and then hypoxia with or without isothermia was applied. Plasma ACTH and corticosterone and mRNA expression of genes for upstream proteins involved in the steroidogenic pathway were measured. Maintenance of isothermia during the prehypoxia period increased baseline plasma ACTH at both ages. Hypothermic hypoxia caused an increase in plasma corticosterone; this response was augmented by isothermia at PD2, when the response was ACTH-independent, and at PD8, when the response was ACTH-dependent. In PD8 rats, isothermia also augmented the plasma ACTH response to hypoxia. We conclude that maintenance of isothermia augments the adrenocortical response to acute hypoxia in the neonate. Prevention of hypothermia may increase the stress response during neonatal hypoxia, becoming more pronounced with increased age.

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The Aging Stress Response and Its Implication for AMD Pathogenesis

International Journal of Molecular Sciences ◽

10.3390/ijms21228840 ◽

2020 ◽

Vol 21 (22) ◽

pp. 8840

Author(s):

Janusz Blasiak ◽

Elzbieta Pawlowska ◽

Anna Sobczuk ◽

Joanna Szczepanska ◽

Kai Kaarniranta

Keyword(s):

Stress Response ◽

Vision Loss ◽

The Elderly ◽

Cellular Level ◽

Age Related Macular Degeneration ◽

Age Related ◽

Evolutionarily Conserved ◽

Nutrient Signaling ◽

Amp Activated Protein Kinase

Aging induces several stress response pathways to counterbalance detrimental changes associated with this process. These pathways include nutrient signaling, proteostasis, mitochondrial quality control and DNA damage response. At the cellular level, these pathways are controlled by evolutionarily conserved signaling molecules, such as 5’AMP-activated protein kinase (AMPK), mechanistic target of rapamycin (mTOR), insulin/insulin-like growth factor 1 (IGF-1) and sirtuins, including SIRT1. Peroxisome proliferation-activated receptor coactivator 1 alpha (PGC-1α), encoded by the PPARGC1A gene, playing an important role in antioxidant defense and mitochondrial biogenesis, may interact with these molecules influencing lifespan and general fitness. Perturbation in the aging stress response may lead to aging-related disorders, including age-related macular degeneration (AMD), the main reason for vision loss in the elderly. This is supported by studies showing an important role of disturbances in mitochondrial metabolism, DDR and autophagy in AMD pathogenesis. In addition, disturbed expression of PGC-1α was shown to associate with AMD. Therefore, the aging stress response may be critical for AMD pathogenesis, and further studies are needed to precisely determine mechanisms underlying its role in AMD. These studies can include research on retinal cells produced from pluripotent stem cells obtained from AMD donors with the mutations, either native or engineered, in the critical genes for the aging stress response, including AMPK, IGF1, MTOR, SIRT1 and PPARGC1A.

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Broadly conserved roles of TMEM131 family proteins in intracellular collagen assembly and secretory cargo trafficking

Science Advances ◽

10.1126/sciadv.aay7667 ◽

2020 ◽

Vol 6 (7) ◽

pp. eaay7667 ◽

Cited By ~ 7

Author(s):

Zhe Zhang ◽

Meirong Bai ◽

Guilherme Oliveira Barbosa ◽

Andrew Chen ◽

Yuehua Wei ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Rna Interference ◽

Caenorhabditis Elegans ◽

Stress Response ◽

Er Stress ◽

C Elegans ◽

Er Stress Response ◽

Evolutionarily Conserved ◽

Human Disorders ◽

Intracellular Collagen

Collagen is the most abundant protein in animals. Its dysregulation contributes to aging and many human disorders, including pathological tissue fibrosis in major organs. How premature collagen proteins in the endoplasmic reticulum (ER) assemble and route for secretion remains molecularly undefined. From an RNA interference screen, we identified an uncharacterized Caenorhabditis elegans gene tmem-131, deficiency of which impairs collagen production and activates ER stress response. We find that amino termini of human TMEM131 contain bacterial PapD chaperone–like domains, which recruit premature collagen monomers for proper assembly and secretion. Carboxy termini of TMEM131 interact with TRAPPC8, a component of the TRAPP tethering complex, to drive collagen cargo trafficking from ER to the Golgi. We provide evidence that previously undescribed roles of TMEM131 in collagen recruitment and secretion are evolutionarily conserved in C. elegans, Drosophila, and humans.

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