AUTHOR=Zhu Shou-Hong , Xue Fei , Li Yan-Jun , Liu Feng , Zhang Xin-Yu , Zhao Lan-Jie , Sun Yu-Qiang , Zhu Qian-Hao , Sun Jie 

TITLE=Identification and Functional Characterization of a Microtubule-Associated Protein, GhCLASP2, From Upland Cotton (Gossypium hirsutum L.)

JOURNAL=Frontiers in Plant Science

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.00882

DOI=10.3389/fpls.2018.00882

ISSN=1664-462X

ABSTRACT=<p>Cytoplasmic linker-associated proteins (CLASPs) are microtubule-associated proteins (MAPs) involved in regulation of dynamics of microtubules (MTs) that play an important role in plant growth and development. In this study, we identified cotton <italic>CLASP</italic> genes and investigated the function of <italic>GhCLASP2</italic>. <italic>GhCLASP2</italic> was mainly expressed in stem and developing fibers, especially in fibers of the secondary cell wall deposition stage. Ectopic expression of <italic>GhCLASP2</italic> in <italic>Arabidopsis</italic> increased the branching number of leaf trichomes and rescued the defective phenotypes of <italic>clasp-1</italic>. In cotton, overexpression of <italic>GhCLASP2</italic> increased fiber strength, probably related to enhanced expression levels of tubulin, cellulose synthase, and expansin genes. Suppression of <italic>GhCLASP2</italic> caused shorter internodes and semi-dwarfism, abnormal flower stigma, aborted anthers without pollen grains, and sterility. These changed phenotypes were similar to those observed in the <italic>Arabidopsis clasp-1</italic> mutant. GhCLASP2 was co-localized with MTs according to transient experiment. These results suggest that <italic>GhCLASP2</italic> functions similarly as <italic>AtCLASP</italic>, acting as a MAP and controlling cotton growth and development by regulating MTs.</p>