The name is absent

modified by ~3 glutamyl residues, binding affinity decreasing with increased
polyglutamyl chain length (Boucher et al., 1994; Larcher et al., 1996). In contrast,
increasing polyglutamyl chain length does not appear to affect the binding affinity
of MAP1A significantly. Bonnet et al. (2001) suggest that the differential binding
of MAPs to polyglutamylated tubulin could facilitate their selective recruitment to
distinct microtubule populations and thereby modulate the functional properties of
microtubules.

Tubulin tail defects and cerebral pathology

British type familial amyloidosis is an autosomal dominant disease characterized
by progressive dementia, spastic paralysis and ataxia. Amyloid deposits from the
brain tissue of an individual who died with this disease have been characterized.
Trypsin digestion and subsequent N-terminal sequence analysis yielded a
number of short sequences, all of which are tryptic fragments of the C-termini of
human α- and β-tubulin. Consistent with the definition of amyloid, synthetic
peptides based on the sequences of these fragments formed fibrils in vitro,
suggesting that the C-termini of both α- and β-tubulin are closely associated with
the amyloid deposits of this type of amyloidosis (Ghiso et al., 1996).

Processing of information by brain microtubules

Taking into account the experimental data from the molecular studies we can
construct biologically feasible model of microtubule processing and integration of
the electrophysiologic information. Microtubule C-termini are both intensely
charged and flexible, so they could undergo conformational transitions separated
by relatively low energy barriers when the strength and the direction of the
electric field vector changes. They are also biochemically regulated via second
messengers coupled to metabotropic receptors (G-protein coupled receptors
known also as 7-TM receptors) and have diverse intraneuronal effects.

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