Loss of GET pathway orthologs inArabidopsis thalianacauses root hair growth defects and affects SNARE abundance

SolubleN-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) proteins are key players in cellular trafficking and coordinate vital cellular processes, such as cytokinesis, pathogen defense, and ion transport regulation. With few exceptions, SNAREs are tail-anchored (TA) proteins, bearing a C-terminal hydrophobic domain that is essential for their membrane integration. Recently, the Guided Entry of Tail-anchored proteins (GET) pathway was described in mammalian and yeast cells that serve as a blueprint of TA protein insertion [Schuldiner M, et al. (2008)Cell134(4):634–645; Stefanovic S, Hegde RS (2007)Cell128(6):1147–1159]. This pathway consists of six proteins, with the cytosolic ATPase GET3 chaperoning the newly synthesized TA protein posttranslationally from the ribosome to the endoplasmic reticulum (ER) membrane. Structural and biochemical insights confirmed the potential of pathway components to facilitate membrane insertion, but the physiological significance in multicellular organisms remains to be resolved. Our phylogenetic analysis of 37 GET3 orthologs from 18 different species revealed the presence of two different GET3 clades. We identified and analyzed GET pathway components inArabidopsis thalianaand found reduced root hair elongation inAtgetlines, possibly as a result of reduced SNARE biogenesis. Overexpression ofAtGET3a in a receptor knockout (KO) results in severe growth defects, suggesting presence of alternative insertion pathways while highlighting an intricate involvement for the GET pathway in cellular homeostasis of plants.

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Faculty Opinions recommendation of A protein kinase target of a PDK1 signalling pathway is involved in root hair growth in Arabidopsis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1020408.234459 ◽

2004 ◽

Author(s):

Jen Sheen

Keyword(s):

Protein Kinase ◽

Root Hair ◽

Hair Growth ◽

Signalling Pathway ◽

Root Hair Growth

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Systematic Humanization of the Yeast Cytoskeleton Discerns Functionally Replaceable from Divergent Human Genes

Genetics ◽

10.1534/genetics.120.303378 ◽

2020 ◽

Vol 215 (4) ◽

pp. 1153-1169 ◽

Cited By ~ 1

Author(s):

Riddhiman K. Garge ◽

Jon M. Laurent ◽

Aashiq H. Kachroo ◽

Edward M. Marcotte

Keyword(s):

Gene Families ◽

Growth Defect ◽

Gene Duplications ◽

Yeast Gene ◽

Macromolecular Transport ◽

Cellular Processes ◽

Growth Defects ◽

Yeast Strains ◽

Human Genes ◽

Interaction Partners

Many gene families have been expanded by gene duplications along the human lineage, relative to ancestral opisthokonts, but the extent to which the duplicated genes function similarly is understudied. Here, we focused on structural cytoskeletal genes involved in critical cellular processes, including chromosome segregation, macromolecular transport, and cell shape maintenance. To determine functional redundancy and divergence of duplicated human genes, we systematically humanized the yeast actin, myosin, tubulin, and septin genes, testing ∼81% of human cytoskeletal genes across seven gene families for their ability to complement a growth defect induced by inactivation or deletion of the corresponding yeast ortholog. In five of seven families—all but α-tubulin and light myosin, we found at least one human gene capable of complementing loss of the yeast gene. Despite rescuing growth defects, we observed differential abilities of human genes to rescue cell morphology, meiosis, and mating defects. By comparing phenotypes of humanized strains with deletion phenotypes of their interaction partners, we identify instances of human genes in the actin and septin families capable of carrying out essential functions, but failing to fully complement the cytoskeletal roles of their yeast orthologs, thus leading to abnormal cell morphologies. Overall, we show that duplicated human cytoskeletal genes appear to have diverged such that only a few human genes within each family are capable of replacing the essential roles of their yeast orthologs. The resulting yeast strains with humanized cytoskeletal components now provide surrogate platforms to characterize human genes in simplified eukaryotic contexts.

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MYB30 and ETHYLENE INSENEITIVE3 antagonistically regulate root hair growth and phosphorus uptake under phosphate deficiency in Arabidopsis

Plant Signaling & Behavior ◽

10.1080/15592324.2021.1913310 ◽

2021 ◽

pp. 1913310

Author(s):

Fei Xiao ◽

Yiyi Zhang ◽

Shuangshuang Zhao ◽

Huapeng Zhou

Keyword(s):

Root Hair ◽

Hair Growth ◽

Phosphorus Uptake ◽

Phosphate Deficiency ◽

Root Hair Growth

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The TOR–Auxin Connection Upstream of Root Hair Growth

Plants ◽

10.3390/plants10010150 ◽

2021 ◽

Vol 10 (1) ◽

pp. 150 ◽

Cited By ~ 1

Author(s):

Katarzyna Retzer ◽

Wolfram Weckwerth

Keyword(s):

Cell Fate ◽

Root Hair ◽

Hair Growth ◽

Environmental Changes ◽

Growth Control ◽

Root Hairs ◽

Signaling Cascades ◽

Continuous Growth ◽

Root Hair Cell ◽

Root Hair Growth

Plant growth and productivity are orchestrated by a network of signaling cascades involved in balancing responses to perceived environmental changes with resource availability. Vascular plants are divided into the shoot, an aboveground organ where sugar is synthesized, and the underground located root. Continuous growth requires the generation of energy in the form of carbohydrates in the leaves upon photosynthesis and uptake of nutrients and water through root hairs. Root hair outgrowth depends on the overall condition of the plant and its energy level must be high enough to maintain root growth. TARGET OF RAPAMYCIN (TOR)-mediated signaling cascades serve as a hub to evaluate which resources are needed to respond to external stimuli and which are available to maintain proper plant adaptation. Root hair growth further requires appropriate distribution of the phytohormone auxin, which primes root hair cell fate and triggers root hair elongation. Auxin is transported in an active, directed manner by a plasma membrane located carrier. The auxin efflux carrier PIN-FORMED 2 is necessary to transport auxin to root hair cells, followed by subcellular rearrangements involved in root hair outgrowth. This review presents an overview of events upstream and downstream of PIN2 action, which are involved in root hair growth control.

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Arabidopsis VILLIN4 is involved in root hair growth through regulating actin organization in a Ca2+-dependent manner

New Phytologist ◽

10.1111/j.1469-8137.2010.03632.x ◽

2011 ◽

Vol 190 (3) ◽

pp. 667-682 ◽

Cited By ~ 42

Author(s):

Yi Zhang ◽

Yingyu Xiao ◽

Fei Du ◽

Lijuan Cao ◽

Huaijian Dong ◽

...

Keyword(s):

Root Hair ◽

Hair Growth ◽

Dependent Manner ◽

Actin Organization ◽

Root Hair Growth

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ROP-GEF signal transduction is involved in AtCAP1-regulated root hair growth

Plant Growth Regulation ◽

10.1007/s10725-018-0448-7 ◽

2018 ◽

Vol 87 (1) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Chongzheng Huang ◽

Xuemiao jiao ◽

Ling Yang ◽

Mimi Zhang ◽

Mengmemg Dai ◽

...

Keyword(s):

Signal Transduction ◽

Root Hair ◽

Hair Growth ◽

Root Hair Growth

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Insertion Defects of Mitochondrially Encoded Proteins Burden the Mitochondrial Quality Control System

Cells ◽

10.3390/cells7100172 ◽

2018 ◽

Vol 7 (10) ◽

pp. 172 ◽

Cited By ~ 2

Author(s):

Braulio Vargas Möller-Hergt ◽

Andreas Carlström ◽

Tamara Suhm ◽

Martin Ott

Keyword(s):

Quality Control ◽

Control System ◽

Mitochondrial Protein ◽

Quality Control System ◽

Yeast Cells ◽

Mitochondrial Quality Control ◽

Protein Insertion ◽

Mitochondrial Proteome ◽

Proteotoxic Stress ◽

Membrane Protein Insertion

The mitochondrial proteome contains proteins from two different genetic systems. Proteins are either synthesized in the cytosol and imported into the different compartments of the organelle or directly produced in the mitochondrial matrix. To ensure proteostasis, proteins are monitored by the mitochondrial quality control system, which will degrade non-native polypeptides. Defective mitochondrial membrane proteins are degraded by membrane-bound AAA-proteases. These proteases are regulated by factors promoting protein turnover or preventing their degradation. Here we determined genetic interactions between the mitoribosome receptors Mrx15 and Mba1 with the quality control system. We show that simultaneous absence of Mrx15 and the regulators of the i-AAA protease Mgr1 and Mgr3 provokes respiratory deficiency. Surprisingly, mutants lacking Mrx15 were more tolerant against proteotoxic stress. Furthermore, yeast cells became hypersensitive against proteotoxic stress upon deletion of MBA1. Contrary to Mrx15, Mba1 cooperates with the regulators of the m-AAA and i-AAA proteases. Taken together, these results suggest that membrane protein insertion and mitochondrial AAA-proteases are functionally coupled, possibly reflecting an early quality control step during mitochondrial protein synthesis.

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