Occludin: a gatekeeper of brain Infection by HIV-1

Table 1 Occludin phosphorylation sites

Kinase	Phosphorylation Site	Model	Mutational analysis	Physiological changes	References
c-Src	Tyr ³⁹⁸, Tyr⁴⁰²,	Rat-1, MDCK (Cell culture	Yes	Regulation of ZO-1, -2, -3.	[99,100,101]
c-Src	Tyr⁴⁷³	MDCK (Cell culture)	No	p85α recruitment.	[102]
CK2	Thr⁴⁰⁰, Thr⁴⁰⁴, Ser⁴⁰⁸	Caco-2, MDCK (Cell culture)	Yes	CK2-mediated barrier regulation. Regulation of ZO-2.	[103] [104]
CK2	Thr³⁷⁵, Ser³⁷⁹	Xenopus laevis	Yes		[105]
cPKC	Ser³³⁸	MDCK (Cell culture)	No		[106]
cPKC	Ser⁴⁹⁰	BREC (in vivo)	No	Inhibits TJ trafficking	[107]
nPKCη	Thr⁴⁰³, Thr⁴⁰⁴, Thr⁴³⁸	Caco-2, MDCK (Cell culture)	Yes	Delays assembly at the TJs	[108, 109]
aPKCζ	Thr⁴²⁴, Thr⁴³⁸, Thr⁴⁰³, Thr⁴⁰⁴	Rat-1, MDCK, Caco-2 (Cell culture)	Yes	Delays assembly at the TJs	[110] [108]
ROCK	Thr³⁸², Ser⁵⁰⁷	COS-7 (Cell culture), BMEC (in vivo)	No		[111]
VEGF	Ser⁴⁹⁰	BREC (Cell culture)	Yes	Inhibits TJ trafficking	[112]

Abbreviations. Ser, serine; Thr, threonine; Tyr, tyrosine; c-Src, cellular tyrosine-protein kinase Src; CK2, casein protein kinase 2; cPKC, conventional protein kinase C; nPKC, novel protein kinase C; aPKC, atypical protein kinase C; VEGF, vascular endothelial growth factor; ROCK, Rho-associated protein kinase; MDCK, Madin Darby canine kidney cells; Caco-2, human colorectal epithelial adenocarcinoma cells; T84, human colon carcinoma cells; BMEC, brain microvascular endothelial cell; BREC, regulatory B cell; COS-7, African green monkey kidney cells (SV40 transformed)

ISSN: 2045-8118