Divergent Functions of the Myotubularin (MTM) Homologs AtMTM1 and AtMTM2 in Arabidopsis thaliana: Evolution of the plant MTM family.
Affiliation
School of Biological Sciences, University of Nebraska at Lincoln, Lincoln NE 68588 USAIssue Date
2012-02-10
Metadata
Show full item recordAbstract
Myotubularin (MTM) and myotubularin related (MTMR) proteins are evolutionary conserved in eukaryotes. Defects in their function result in muscle dystrophy, neuronal diseases and leukemia in humans. In contrast to the animal lineage where genes encoding both active and inactive myotubularins (phosphoinositide 3-phosphatases) have appeared and proliferated in the basal metazoan group, myotubularin genes are not found in the unicellular relatives of green plants. However, they are present in land plants encoding proteins highly similar to the active metazoan enzymes. Despite the remarkable structural conservation, plant and animal myotubularins have significantly diverged in their functions. While loss of myotubularin function causes severe disease phenotypes in humans it is not essential for the cellular homeostasis under normal conditions in Arabidopsis thaliana. Instead, myotubularin deficiency is associated with altered tolerance to dehydration stress. The two Arabidopsis genes AtMTM1 and AtMTM2 have originated from a segmental chromosomal duplication and encode catalytically active enzymes. However, only AtMTM1 is involved in elevating the cellular level of phosphatidylinositol 5-phosphate (PtdIns5P) in response to dehydration stress and the two myotubularins differentially affect the Arabidopsis dehydration stress-responding transcriptome. AtMTM1 and AtMTM2 display different localization patterns in the cell consistent with the idea that they associate with different membranes to perform specific functions. A single amino acid mutation in AtMTM2 (L250W) results in a dramatic loss of subcellular localization. Mutations in this region are linked to disease conditions in humans. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.Citation
Divergent Functions of the Myotubularin (MTM) Homologs AtMTM1 and AtMTM2 in Arabidopsis thaliana: Evolution of the plant MTM family. 2012:Plant JJournal
The Plant JournalDOI
10.1111/j.1365-313X.2012.04936.xPubMed ID
22324391Type
ArticleLanguage
enISSN
1365-313Xae974a485f413a2113503eed53cd6c53
10.1111/j.1365-313X.2012.04936.x
Scopus Count
Collections
Related articles
- Subcellular localizations of Arabidopsis myotubularins MTM1 and MTM2 suggest possible functions in vesicular trafficking between ER and cis-Golgi.
- Authors: Nagpal A, Ndamukong I, Hassan A, Avramova Z, Baluška F
- Issue date: 2016 Aug 1
- The Arabidopsis chromatin modifier ATX1, the myotubularin-like AtMTM and the response to drought.
- Authors: Ding Y, Lapko H, Ndamukong I, Xia Y, Al-Abdallat A, Lalithambika S, Sadder M, Saleh A, Fromm M, Riethoven JJ, Lu G, Avramova Z
- Issue date: 2009 Nov
- Myotubularins, PtdIns5P, and ROS in ABA-mediated stomatal movements in dehydrated Arabidopsis seedlings.
- Authors: Nagpal A, Hassan A, Ndamukong I, Avramova Z, Baluška F
- Issue date: 2018 Jan
- Phosphatidylinositol 5-phosphate links dehydration stress to the activity of ARABIDOPSIS TRITHORAX-LIKE factor ATX1.
- Authors: Ndamukong I, Jones DR, Lapko H, Divecha N, Avramova Z
- Issue date: 2010 Oct 13
- AtMTM1, a novel mitochondrial protein, may be involved in activation of the manganese-containing superoxide dismutase in Arabidopsis.
- Authors: Su Z, Chai MF, Lu PL, An R, Chen J, Wang XC
- Issue date: 2007 Sep