Physio-pathological roles of transglutaminase-catalyzed reactions

Table 2 List of polyglutamine (CAG-expansion) diseases

Disease	Sites of neuropathology	CAG triplet number		Gene product (Intracellular localization of protein deposits)	Ref.
		Normal	Disease
Corea major or HD	Striatum (medium spiny neurons) and cortex in late stage	6-35	36-121	Huntingtin (n, c)	[44]
SCA1	Cerebellar cortex (Purkinje cells), dentate nucleus and brain stem	6-39	40-81	Ataxin-1 (n, c)	[45]
SCA2	Cerebellum, pontine nuclei, substantia nigra	15-29	35-64	Ataxin-2 (c)	[46]
SCA3 or MJD	Substantia nigra, globus pallidus, pontine nucleus, cerebellar cortex	13-42	61-84	Ataxin-3 (c)	[47]
SCA6	Cerebellar and mild brainstem atrophy	4-18	21-30	Calcium channel	[48]
				Subunit (a1A) (m)
SCA7	Photoreceptor and bipolar cells, cerebellar cortex, brainstem	7-17	37-130	Ataxin-7 (n)	[49]
SCA12	Cortical, cerebellar atrophy	7-32	41-78	Brain specific regulatory subunit of protein phosphatase PP2A (?)	[50]
SCA17	Gliosis and neuronal loss in the Purkinje cell layer	29-42	46-63	TATA-binding protein (TBP) (n)	[51]
SBMA or Kennedy disease	Motor neurons (anterior horn cells, bulbar neurons) and dorsal root ganglia	11-34	40-62	Androgen receptor (n, c)	[52]
DRPLA	Globus pallidus, dentato-rubral and subthalamic nucleus	7-35	49-88	Atrophin (n, c)	[53]

HD: Huntington’s disease; SCA: Spinocerebellar ataxia; MJD: Machado-Joseph disease; SBMA: Spinobulbar muscular atrophy; DRPLA: Dentatorubral-pallidoluysian atrophy; c: Cytosolic; m: Transmembrane; n: Nuclear.