TY - JOUR
T1 - Mutations in the Pectin Methyltransferase QUASIMODO2 influence cellulose biosynthesis and wall integrity in arabidopsis
AU - Du, Juan
AU - Kirui, Alex
AU - Huang, Shixin
AU - Wang, Lianglei
AU - Barnes, William J.
AU - Kiemle, Sarah N.
AU - Zheng, Yunzhen
AU - Rui, Yue
AU - Ruan, Mei
AU - Qi, Shiqian
AU - Kim, Seong H.
AU - Wang, Tuo
AU - Cosgrove, Daniel J.
AU - Anderson, Charles T.
AU - Xiao, Chaowen
N1 - Funding Information:
AnalysisofQUA2proteinactivitywassupportedbyFundamentalResearch Funds for the Central Universities (grants YJ20173 and SCU2019D013 to C.X.), and the China Postdoctoral Science Foundation (grant 2018M643465 to J.D.).
Funding Information:
We thank Liza Wilson and Sydney Duncombe for technical assistance with AFM experiments, Tanya Falbel for providing seeds of qua2 and tsd2 mutants, Richard Cyr for providing the GFP-MAP4 expression construct, and Nicole R. Brown for helpful comments on the article. With the exceptions below, this work was supported as part of The Center for Lignocellulose Structure and Formation, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences (grant DE-SC0001090 to S.K., D.J.C., and C.T.A.).
Publisher Copyright:
© 2020 ASPB.
PY - 2020/11
Y1 - 2020/11
N2 - Pectins are abundant in the cell walls of dicotyledonous plants, but how they interact with other wall polymers and influence wall integrity and cell growth has remained mysterious. Here, we verified that QUASIMODO2 (QUA2) is a pectin methyltransferase and determined that QUA2 is required for normal pectin biosynthesis. To gain further insight into how pectin affects wall assembly and integrity maintenance, we investigated cellulose biosynthesis, cellulose organization, cortical microtubules, and wall integrity signaling in two mutant alleles of Arabidopsis (Arabidopsis thaliana) QUA2, qua2 and tsd2. In both mutants, crystalline cellulose content is reduced, cellulose synthase particles move more slowly, and cellulose organization is aberrant. NMR analysis shows higher mobility of cellulose and matrix polysaccharides in the mutants. Microtubules in mutant hypocotyls have aberrant organization and depolymerize more readily upon treatment with oryzalin or external force. The expression of genes related to wall integrity, wall biosynthesis, and microtubule stability is dysregulated in both mutants. These data provide insights into how homogalacturonan is methylesterified upon its synthesis, the mechanisms by which pectin functionally interacts with cellulose, and how these interactions are translated into intracellular regulation to maintain the structural integrity of the cell wall during plant growth and development.
AB - Pectins are abundant in the cell walls of dicotyledonous plants, but how they interact with other wall polymers and influence wall integrity and cell growth has remained mysterious. Here, we verified that QUASIMODO2 (QUA2) is a pectin methyltransferase and determined that QUA2 is required for normal pectin biosynthesis. To gain further insight into how pectin affects wall assembly and integrity maintenance, we investigated cellulose biosynthesis, cellulose organization, cortical microtubules, and wall integrity signaling in two mutant alleles of Arabidopsis (Arabidopsis thaliana) QUA2, qua2 and tsd2. In both mutants, crystalline cellulose content is reduced, cellulose synthase particles move more slowly, and cellulose organization is aberrant. NMR analysis shows higher mobility of cellulose and matrix polysaccharides in the mutants. Microtubules in mutant hypocotyls have aberrant organization and depolymerize more readily upon treatment with oryzalin or external force. The expression of genes related to wall integrity, wall biosynthesis, and microtubule stability is dysregulated in both mutants. These data provide insights into how homogalacturonan is methylesterified upon its synthesis, the mechanisms by which pectin functionally interacts with cellulose, and how these interactions are translated into intracellular regulation to maintain the structural integrity of the cell wall during plant growth and development.
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U2 - 10.1105/TPC.20.00252
DO - 10.1105/TPC.20.00252
M3 - Article
C2 - 32883711
AN - SCOPUS:85095461764
VL - 32
SP - 3576
EP - 3597
JO - Plant Cell
JF - Plant Cell
SN - 1040-4651
IS - 11
ER -