The name is absent

Tubulin C-termini biological function

C-termini of α- and β- tubulin known as tubulin "tails" are rich in acidic aminoacid
residues (Krauhs et al., 1981; Ponstingl et al., 1981) that is why the C-termini are
highly flexible, mobile, susceptible to proteolysis, and exposed to the solvent
(Sarkar et al., 2001; Tuszynski, 2003). Because of their intense charge and high
flexibility the tubulin C-termini could be sensitive to the local electric field and
input the carried by the membrane potentials information. This hypothesis is
further supported by the experimental data showing that the highly acidic tubulin
C-termini interact with motor proteins and microtubule associated proteins
(MAPs). Fujii & Kozumi (1999) studied the associations of MAPs with tubulin.
They found tubulin to undergo many posttranslational modifications at or near the
carboxyl termini of the subunits. These carboxyl termini are rich in acidic amino
acids and have been shown to be involved in tubulin binding to MAPs.
Specifically, they found the MAPs to bind α-tubulin at amino acid sequences
Lys430-Glu441 and β-tubulin at amino acid sequences Tyr 422-Gly 434.

Rai & Wolff (1998) report that the β-tubulin C-terminus binds microtubule-
associated protein 2 (MAP-2) or tau, whereas the α-tubulin C terminus binds
these proteins only weakly. The α-tubulin C-terminus determines colchicine-
binding properties (Mukhopadhyay et al., 1990) despite the fact that the binding
site is located on β-tubulin (Uppuluri et al., 1993; Bai et al., 1996). When
colchicine is delivered directly to the brain or cerebrospinal fluid of experimental
animals it causes significant cognitive impairments of learning and memory
(Bensimon & Chernat, 1991; Kolasa et al., 1992).

The β-tubulin C-terminus enhances the polymerization response to vinblastine,
while the removal of the β-tubulin C-terminus abolishes the inhibitory effect of
oligoanions on vinblastine-induced polymerization (Rai & Wolff, 1998). The
C-termini of tubulin play a role in the dimer-polymer equilibrium (Sackett et al.,

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