Primary Information
BoMiProt ID	Bomi251
Protein Name	Claudin-3
Organism	Bos taurus
Uniprot ID	Q765N9
Milk Fraction	Exosome
Ref Sequence ID	NP_991370.1
Aminoacid Length	219
Molecular Weight	23382
FASTA Sequence	Download
Gene Name	CLDN3
Gene ID	404153
Protein Existence Status	Reviewed: Experimental evidence at transcript level
Secondary Information
Protein Function	tetraspan transmembrane proteins of tight junctions; regulate strength of tight junctions. The tight junction protein claudin-3 has been identified as a transcriptional target of the Wnt/β-catenin signaling pathway regulating blood-brain barrier (BBB) maturation.
Significance in milk	maintain the integrity of the alveolar structure during lactation
PTMs	protein kinase A in claudin-3 (Thr192, human)
Site(s) of PTM(s) N-glycosylation, O-glycosylation, Phosphorylation
Predicted Disorder Regions	NA
DisProt Annotation
TM Helix Prediction	4TMHs; (7-29), (78-100), (121-143), (163-185)
Significance of PTMs	Phosphorylation of claudin-3 may decrease the tight junction strength in ovarian cancer cells
Additional Comments	In neurological disorders loss of claudin-3 immunostaining is observed at the compromised BBB and blood-cerebrospinal fluid barrier (BCSFB).
Bibliography	1. Soma, T. et al. (2004) ‘Thr207 of claudin-5 is involved in size-selective loosening of the endothelial barrier by cyclic AMP’, Experimental Cell Research, 300(1), pp. 202–212. doi: 10.1016/j.yexcr.2004.07.012. 2. D’Souza, T., Agarwal, R. and Morin, P. J. (2005) ‘Phosphorylation of Claudin-3 at Threonine 192 by cAMP-dependent Protein Kinase Regulates Tight Junction Barrier Function in Ovarian Cancer Cells’, Journal of Biological Chemistry, 280(28), pp. 26233–26240. doi: 10.1074/jbc.M502003200. 3. Pitelka, D. R. et al. (1973) ‘CELL CONTACTS IN THE MOUSE MAMMARY GLAND: I. Normal Gland in Postnatal Development and the Secretory Cycle’, The Journal of Cell Biology, 56(3), pp. 797–818. doi: 10.1083/jcb.56.3.797. 4.Castro Dias M, Coisne C, Lazarevic I, Baden P, Hata M, Iwamoto N, Francisco DMF, Vanlandewijck M, He L, Baier FA, Stroka D, Bruggmann R, Lyck R, Enzmann G, Deutsch U, Betsholtz C, Furuse M, Tsukita S, Engelhardt B. Claudin-3-deficient C57BL/6J mice display intact brain barriers. Sci Rep. 2019 Jan 18;9(1):203. doi: 10.1038/s41598-018-36731-3. Erratum in: Sci Rep. 2019 Jul 18;9(1):10702. PMID: 30659216; PMCID: PMC6338742.