A Myosin-like Protein from a Higher Plant

• Published in: Journal of molecular biology Vol. 231; no. 1; pp. 148 - 154
• Main Authors: Knight, Alex E., Kendrick-Jones, John
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 05.05.1993; Elsevier
• Subjects: Amino Acid Sequence; Animals; Arabidopsis; Arabidopsis - genetics; Base Sequence; Biological and medical sciences; Blotting, Northern; calmodulin. molecular motor; Chemical constitution; Cloning, Molecular; coiled-coil; DNA - genetics; DNA - isolation & purification; Fundamental and applied biological sciences. Psychology; Gene Library; Molecular Sequence Data; Molecular Weight; myosin; Myosins - genetics; Myosins - isolation & purification; Oligodeoxyribonucleotides; Phylogeny; Plant physiology and development; Plant Proteins - genetics; Plant Proteins - isolation & purification; Poly A - genetics; Poly A - isolation & purification; Polymerase Chain Reaction; Restriction Mapping; RNA - genetics; RNA - isolation & purification; RNA, Messenger; Sequence Homology, Amino Acid; myosin; coiled-coil; calmodulin. molecular motor; Arabidopsis; Nucleotide sequence; Contractile protein; Homology; Arabidopsis thaliana; Molecular evolution; Complementary DNA; Structural unit; Cruciferae; Dicotyledones; Angiospermae; Myosin; Spermatophyta; Aminoacid sequence
• ISSN: 0022-2836; 1089-8638
• DOI: 10.1006/jmbi.1993.1266

As part of a study of the diversity of myosins, we have cloned a cDNA encoding a myosin-like protein from Arabidopsis thaliana. This is the first molecular motor of any kind to be cloned from a higher plant. The predicted polypeptide (molecular weight 131 kDa) has a motor domain (head) very similar to those of other myosins, but the remainder of the sequence is unusual. The tail contains four potential calmodulin binding sites ("IQ-motifs"), but no sequence motifs suggestive of actin or phospholipid binding, like those found in other myosins. There is also a small region of probable α-helical coiled-coil, which suggests that the molecule could be dimeric, though unlikely to form filaments. The N-terminal and C-terminal regions of the molecule are unique. We present a phylogenetic analysis of myosin head sequences, which suggests that this is a new type of myosin.