| Structural highlights
Function
[MPK6_ARATH] Involved in oxidative stress-mediated signaling cascade (such as ozone). Involved in the innate immune MAP kinase signaling cascade (MEKK1, MKK4/MKK5 and MPK3/MPK6) downstream of bacterial flagellin receptor FLS2. May be involved in hypersensitive response (HR)-mediated signaling cascade by modulating LIP5 phosphorylation and subsequent multivesicular bodies (MVBs) trafficking. May phosphorylate regulators of WRKY transcription factors. Phosphorylates 1-aminocyclopropane-1-carboxylic acid synthases (ACS2 and ACS6) and may be involved in the regulation of bacterial elicitor flagellin-induced ethylene production. Regulates locally gene-mediated and basal resistance response to certain pathogens. May be involved in the cold and salinity stress-mediated MAP kinase signaling cascade (MEKK1, MKK1/MKK2 and MPK4/MPK6). MKK1-MPK6 module mediates abscisic acid (ABA)-dependent CAT1 expression with H(2)O(2) production and response to drought and salt stress. MKK1-MPK6 module is also involved in sugar signaling during the process of seed germination. MKK3-MPK6 module plays an important role in the jasmonate signal transduction pathway through the negative regulation of MYC2/JIN1 expression. MKK9-MPK3/MPK6 module phosphorylates and activates EIN3, leading to the promotion of EIN3-mediated transcription in ethylene signaling. MPK3/MPK6 cascade regulates camalexin synthesis through transcriptional regulation of the biosynthetic genes after pathogen infection. MKK9-MPK6 module positively regulates leaf senescence. YDA-MKK4/MKK5-MPK3/MPK6 module regulates stomatal cell fate before the guard mother cell (GMC) is specified. This MAPK cascade also functions downstream of the ER receptor in regulating coordinated local cell proliferation, which shapes the morphology of plant organs.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
Publication Abstract from PubMed
Cell fate in eukaryotes is controlled by mitogen-activated protein kinases (MAPKs) that translate external cues into cellular responses. In plants, two MAPKs-MPK3 and MPK6-regulate diverse processes of development, environmental response and immunity. However, the mechanism that bridges these shared signalling components with a specific target remains unresolved. Focusing on the development of stomata-epidermal valves that are essential for gas exchange and transpiration-here, we report that the basic helix-loop-helix protein SCREAM functions as a scaffold that recruits MPK3/6 to downregulate SPEECHLESS, a transcription factor that initiates stomatal cell lineages. SCREAM directly binds to MPK3/6 through an evolutionarily conserved, yet unconventional, bipartite motif. Mutations in this motif abrogate association, phosphorylation and degradation of SCREAM, unmask hidden non-redundancies between MPK3 and MPK6, and result in uncontrolled stomatal differentiation. Structural analyses of MPK6 with a resolution of 2.75 A showed bipartite binding of SCREAM to MPK6 that is distinct from an upstream MAPKK. Our findings elucidate, at the atomic resolution, the mechanism that directly links extrinsic signals to transcriptional reprogramming during the establishment of stomatal cell fate, and highlight a unique substrate-binding mode adopted by plant MAPKs.
Bipartite anchoring of SCREAM enforces stomatal initiation by coupling MAP kinases to SPEECHLESS.,Putarjunan A, Ruble J, Srivastava A, Zhao C, Rychel AL, Hofstetter AK, Tang X, Zhu JK, Tama F, Zheng N, Torii KU Nat Plants. 2019 Jul;5(7):742-754. doi: 10.1038/s41477-019-0440-x. Epub 2019 Jun , 24. PMID:31235876[15]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Asai T, Tena G, Plotnikova J, Willmann MR, Chiu WL, Gomez-Gomez L, Boller T, Ausubel FM, Sheen J. MAP kinase signalling cascade in Arabidopsis innate immunity. Nature. 2002 Feb 28;415(6875):977-83. PMID:11875555 doi:http://dx.doi.org/10.1038/415977a
- ↑ Menke FL, van Pelt JA, Pieterse CM, Klessig DF. Silencing of the mitogen-activated protein kinase MPK6 compromises disease resistance in Arabidopsis. Plant Cell. 2004 Apr;16(4):897-907. Epub 2004 Mar 12. PMID:15020743 doi:http://dx.doi.org/10.1105/tpc.015552
- ↑ Teige M, Scheikl E, Eulgem T, Doczi R, Ichimura K, Shinozaki K, Dangl JL, Hirt H. The MKK2 pathway mediates cold and salt stress signaling in Arabidopsis. Mol Cell. 2004 Jul 2;15(1):141-52. PMID:15225555 doi:http://dx.doi.org/10.1016/j.molcel.2004.06.023
- ↑ Liu Y, Zhang S. Phosphorylation of 1-aminocyclopropane-1-carboxylic acid synthase by MPK6, a stress-responsive mitogen-activated protein kinase, induces ethylene biosynthesis in Arabidopsis. Plant Cell. 2004 Dec;16(12):3386-99. Epub 2004 Nov 11. PMID:15539472 doi:http://dx.doi.org/tpc.104.026609
- ↑ Miles GP, Samuel MA, Zhang Y, Ellis BE. RNA interference-based (RNAi) suppression of AtMPK6, an Arabidopsis mitogen-activated protein kinase, results in hypersensitivity to ozone and misregulation of AtMPK3. Environ Pollut. 2005 Nov;138(2):230-7. PMID:15964670 doi:http://dx.doi.org/S0269-7491(05)00226-5
- ↑ Wang H, Ngwenyama N, Liu Y, Walker JC, Zhang S. Stomatal development and patterning are regulated by environmentally responsive mitogen-activated protein kinases in Arabidopsis. Plant Cell. 2007 Jan;19(1):63-73. Epub 2007 Jan 26. PMID:17259259 doi:http://dx.doi.org/10.1105/tpc.106.048298
- ↑ Takahashi F, Yoshida R, Ichimura K, Mizoguchi T, Seo S, Yonezawa M, Maruyama K, Yamaguchi-Shinozaki K, Shinozaki K. The mitogen-activated protein kinase cascade MKK3-MPK6 is an important part of the jasmonate signal transduction pathway in Arabidopsis. Plant Cell. 2007 Mar;19(3):805-18. Epub 2007 Mar 16. PMID:17369371 doi:http://dx.doi.org/10.1105/tpc.106.046581
- ↑ Xing Y, Jia W, Zhang J. AtMKK1 mediates ABA-induced CAT1 expression and H2O2 production via AtMPK6-coupled signaling in Arabidopsis. Plant J. 2008 May;54(3):440-51. doi: 10.1111/j.1365-313X.2008.03433.x. Epub 2008 , Jan 31. PMID:18248592 doi:http://dx.doi.org/10.1111/j.1365-313X.2008.03433.x
- ↑ Yoo SD, Cho YH, Tena G, Xiong Y, Sheen J. Dual control of nuclear EIN3 by bifurcate MAPK cascades in C2H4 signalling. Nature. 2008 Feb 14;451(7180):789-95. doi: 10.1038/nature06543. PMID:18273012 doi:http://dx.doi.org/10.1038/nature06543
- ↑ Ren D, Liu Y, Yang KY, Han L, Mao G, Glazebrook J, Zhang S. A fungal-responsive MAPK cascade regulates phytoalexin biosynthesis in Arabidopsis. Proc Natl Acad Sci U S A. 2008 Apr 8;105(14):5638-43. doi:, 10.1073/pnas.0711301105. Epub 2008 Mar 31. PMID:18378893 doi:http://dx.doi.org/10.1073/pnas.0711301105
- ↑ Zhou C, Cai Z, Guo Y, Gan S. An arabidopsis mitogen-activated protein kinase cascade, MKK9-MPK6, plays a role in leaf senescence. Plant Physiol. 2009 May;150(1):167-77. doi: 10.1104/pp.108.133439. Epub 2009 Feb , 27. PMID:19251906 doi:http://dx.doi.org/10.1104/pp.108.133439
- ↑ Xing Y, Jia W, Zhang J. AtMKK1 and AtMPK6 are involved in abscisic acid and sugar signaling in Arabidopsis seed germination. Plant Mol Biol. 2009 Aug;70(6):725-36. doi: 10.1007/s11103-009-9503-0. Epub 2009 , May 31. PMID:19484493 doi:http://dx.doi.org/10.1007/s11103-009-9503-0
- ↑ Meng X, Wang H, He Y, Liu Y, Walker JC, Torii KU, Zhang S. A MAPK cascade downstream of ERECTA receptor-like protein kinase regulates Arabidopsis inflorescence architecture by promoting localized cell proliferation. Plant Cell. 2012 Dec;24(12):4948-60. doi: 10.1105/tpc.112.104695. Epub 2012 Dec, 21. PMID:23263767 doi:http://dx.doi.org/10.1105/tpc.112.104695
- ↑ Wang F, Shang Y, Fan B, Yu JQ, Chen Z. Arabidopsis LIP5, a positive regulator of multivesicular body biogenesis, is a critical target of pathogen-responsive MAPK cascade in plant basal defense. PLoS Pathog. 2014 Jul 10;10(7):e1004243. doi: 10.1371/journal.ppat.1004243., eCollection 2014 Jul. PMID:25010425 doi:http://dx.doi.org/10.1371/journal.ppat.1004243
- ↑ Putarjunan A, Ruble J, Srivastava A, Zhao C, Rychel AL, Hofstetter AK, Tang X, Zhu JK, Tama F, Zheng N, Torii KU. Bipartite anchoring of SCREAM enforces stomatal initiation by coupling MAP kinases to SPEECHLESS. Nat Plants. 2019 Jul;5(7):742-754. doi: 10.1038/s41477-019-0440-x. Epub 2019 Jun , 24. PMID:31235876 doi:http://dx.doi.org/10.1038/s41477-019-0440-x
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