Effects of Plasma Membrane Localization of Arabidopsis thaliana CBL9 on the Growth of Pollen Tube Tip

doi:10.13560/j.cnki.biotech.bull.1985.2018-1093

Abstract

Abstract: This work is aimed to understand the role of Arabidopsis thaliana CBL9（calcineurin B-like protein 9）in the growth of pollen tube tip. Based on the transient expression system,the CBL9 with YFP-tag were transiently expressed in tobacco pollen grains by gene gun,and the overexpression phenotypes and subcellular localization patterns of CBL9-YFP were observed. At the conservative sites for N-terminal acylation of CBL9,a mutant version of CBL9,CBL9G2A was constructed via overlap-PCR-mediated site mutagenesis,and the changes in their phenotypes and localization were compared and studied. The results demonstrated that CBL9-YFP was localized to plasma membrane（PM）of growing pollen tubes and granular organelles. CBL9 overexpression induced a severe loss of growth polarity,leading to a short tube with the swelling tip. CBL9G2A was evenly distributed in cytosol of pollen tubes,and its overexpression did not cause the depolarization growth of pollen tubes. These results suggested that N-terminal acylation site of CBL9 is an important factor in correct targeting to PM,which is required for its function in polarized growth of pollen tubes.

Key words: Arabidopsis thaliana, pollen tube, tip growth, calcium, calcineurin B-like protein

ZHOU Li-ming, FANG Wei. Effects of Plasma Membrane Localization of Arabidopsis thaliana CBL9 on the Growth of Pollen Tube Tip[J]. Biotechnology Bulletin, 2019, 35(5): 58-63.

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