Arabidopsis CROLIN1, a novel plant actin-binding protein, functions in cross-linking and stabilizing actin filaments.
Higher order actin filament structures are necessary for cytoplasmic streaming, organelle movement, and other physiological processes. However, the mechanism by which the higher order cytoskeleton is formed in plants remains unknown. In this study, we identified a novel actin-cross-linking protein family (named CROLIN) that is well conserved only in the plant kingdom. There are six isovariants of CROLIN in the Arabidopsis genome, with CROLIN1 specifically expressed in pollen. In vitro biochemical analyses showed that CROLIN1 is a novel actin-cross-linking protein with binding and stabilizing activities. Remarkably, CROLIN1 can cross-link actin bundles into actin networks. CROLIN1 loss of function induces pollen germination and pollen tube growth hypersensitive to latrunculin B. All of these results demonstrate that CROLIN1 may play an important role in stabilizing and remodeling actin filaments by binding to and cross-linking actin filaments.
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Honglei
H
Jia
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Jisheng
J
Li
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Jingen
J
Zhu
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Tingting
T
Fan
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Dong
D
Qian
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
Yuelong
Y
Zhou
the Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing 100875, China.
Jiaojiao
J
Wang
the Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing 100875, China.
Haiyun
H
Ren
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China. Electronic address: xiangy@lzu.edu.cn.
Yun
Y
Xiang
From the Key Laboratory of Cell Activities and Stress Adaptations of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China. Electronic address: lizhean@lzu.edu.cn.
Lizhe
L
An
D000199:Actins / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D053205:Pollen Tube / Q000235:genetics / Q000378:metabolism*
D000199:Actins; D029681:Arabidopsis Proteins; D008840:Microfilament Proteins
Actin; Actin-cross-linking Protein; Arabidopsis; CROLIN1; Cell Polarity; Novel Actin-binding Protein; Plant; Plant Biochemistry