Myosin genes in Tetrahymena.

This report presents an initial comparison of motor, neck, and tail domains of myosin genes in Tetrahymena thermophila. An unrooted phylogenetic tree drawn from alignment of predicted amino acid translations determined the relationship among 13 myosins in Tetrahymena and their relationship to the myosin superfamily. The myosins in Tetrahymena did not align with any of the previously named myosin classes. Twelve of the Tetrahymena myosins form a new class designated as XX. The other Tetrahymena myosin is divergent from the twelve. Surprisingly, none of the myosins in Tetrahymena aligned with either class I, class II, or class V myosins. Apparent absence of a class II myosin is an indication that cytokinesis in Tetrahymena either utilizes an unconventional myosin or does not require a myosin motor. Copyright (c) 2005 Wiley-Liss, Inc.