ABCMdb

PMID: 19642168

Keitel V, Burdelski M, Vojnisek Z, Schmitt L, Haussinger D, Kubitz R
De novo bile salt transporter antibodies as a possible cause of recurrent graft failure after liver transplantation: a novel mechanism of cholestasis.
Hepatology. 2009 Aug;50(2):510-7., [PubMed]

Sentences

No. Mutations Sentence Comment

29 ABCB11 p.Val444Ala ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe Compared to the reference sequence NM_003742 of BSEP (ABCB11), three homozygous missense changes were found: 1331T3C (V444A),17 2453A3T (Y818F), and 2944G3A (G982R)4 (start codon numbered as "1"). Login to comment 79 ABCB11 p.Val444Ala The construct contained three silent mutations (2190G3A, 3210A3G, 3516C3C) and one mutation (1331T3C), leading to an amino acid replacement (V444A). Login to comment 81 ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe The patient`s mutations were introduced using the Quickchange-Multisite- mutagenesis kit (Stratagene) and the following primers: 2453A3T (Y818F): 5Ј-ccaatttctacagggatttgcctttgctaaatc- 3Ј; 2944G3A (G982R): 5Ј-cagaaagccaatatttacagattctgctt- tgcctttgc-3Ј. Login to comment 150 ABCB11 p.Val444Ala ABCB11 p.Tyr818Phe ABCB11 p.Tyr818Phe Introduction of the mutations V444A or Y818F separately or together into BSEP-YFP had no apparent effect on the localization of BSEPV444A, BSEPY818F, or BSEPV444A/Y818F as compared to wild-type BSEP-YFP (Fig. 2A, 4A). Login to comment 151 ABCB11 p.Val444Ala ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe However, introduction of G982R alone or in combination with either V444A or Y818F (Fig. 4B) resulted in the retention of BSEPG982R, BSEPV444A/G982R, and BSEPY818F/G982R in the endoplasmic reticulum (ER) in colocalization with the ER marker protein disulfide isomerase. Login to comment 152 ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe Combining all three mutations resulted in nondetectability of BSEPV444A/Y818F/G982R-YFP (Fig. 4C) independent of the cell type used (Supporting Fig. 3). Login to comment 154 ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe Unexpectedly, K165 and K168 immunoreactivity, but no YFP fluorescence, was present in aggresomes of BSEPV444A/Y818F/ G982R-YFP-transfected cells after MG-132 treatment (Fig. 4G,J). Login to comment 165 ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe Bars ϭ 10 ␮m. BSEPV444A/Y818F/G982R-YFP within the ER-associated degradation pathway. Login to comment 166 ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe Furthermore, the apparent loss of YFP fluorescence is suggestive of an incomplete expression or a major folding defect of BSEPV444A/Y818F/G982R-YFP. Login to comment 175 ABCB11 p.Val444Ala ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe It is of note, that in addition to the G982R and Y818F mutations, the common mutation/polymorphism V444A is necessary for the complete disappearance of BSEP. Login to comment 176 ABCB11 p.Val444Ala ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe V444A has a high prevalence in the Caucasian population,17 has been linked to the development of drug-induced liver injury,30 and may aggravate cholestatic liver diseases such as intrahepatic cholestasis of pregnan- cy31 or benign recurrent intrahepatic cholestasis.32 Expression of BSEPV444A/Y818F/G982R in hepatic and nonhepatic cell lines was below detectability. Login to comment 184 ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe The presence of G982R and Y818F caused the retention of mutated BSEPY818F/G982R-YFP within the endoplasmic reticulum. Login to comment 185 ABCB11 p.Val444Ala ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe ABCB11 p.Tyr818Phe Combination of all three mutations of the patient (V444A,Y818F,G982R) induced complete absence of mutated BSEPV444A/Y818F/G982R-YFP. Login to comment 188 ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Gly982Arg ABCB11 p.Tyr818Phe ABCB11 p.Tyr818Phe ABCB11 p.Tyr818Phe ABCB11 p.Tyr818Phe (G-L) Aggresomes, induced by MG132 in BSEPV444A/Y818F/G982R-YFP-expressing cells, contained immunoreactivity for the BSEP antibodies K165 (I) and K168 (L) but no green fluorescence, suggesting incomplete expression or misfolding of BSEPV444A/Y818F/G982R-YFP. Login to comment