Table I. Native and chimeric β-tubulins tested in the post-mitotic male germ cells.

The carboxy termini of β2-tubulin, β1-tubulin and the reciprocal chimeric tubulins are shown. Sequences in the body of the chimeric β-tubulins are identical to the native sequences. The variable carboxyl-terminal tail (CTT) consists of the last 15 amino acids of β2 and the last 16 amino acids of β1. The β2 axoneme motif is underlined [Raff et al., 1997]. The β1 CTT does not contain an axoneme motif. Based on the 3-dimensional model for porcine brain tubulins [Nogales et al., 1998, 1999], the unresolved or ‘flexible’ region of the β-tubulin carboxyl terminus begins at position 428 in Drosophila β2 and β1.

β-tubulin	“Body” of the molecule	Source of C-terminal tail	C-terminal tail sequence	Reference
β2	β2	β2	EEGEFDEDEEGGGDE446	Rudolph et al., 1987; Hoyle et al., 1995
β1	β1	β1	EDAEFEEEQEAEVDEN447	Raff et al., 2000; Nielsen et al., 2001
β1β2C	β1	β2	EEGEFDEDEEGGGDE446	Nielsen et al., 2001
β2β1C	β2	β1	EDAEFEEEQEAEVDEN447	Popodi et al., 2008