caa a22 4500 477082556 CHVBK 20180405111454.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF01938869 doi (NATIONALLICENCE)springer-10.1007/BF01938869 Critical amino-terminal segments in insertion of rat liver cytochrome P450 3A1 into the endoplasmic reticulum membrane [Elektronische Daten] [P. Van den Broek, M. Barroso, M. Lechner] An in vitro transcription-translation assay was used to study the membrane topology of rat liver cytochrome P450 3A1. N-terminus deletion mutants were constructed to assess the importance of N-terminal regions in the stable incorporation of the protein into the microsomal membranes. Wild-type nascent cytochrome P450 bound to microsomes as an integral membrane protein through its hydrophobic N-terminal segments, uncleaved by signal peptidase. Deletion of the most N-terminal hydrophobic segment (positions 7-26) had a dramatic effect on endoplasmic reticulum membrane integration. Confirming the essential role of this stretch in P450 3A1 membrane targeting, proteolysis-resistant membrane-associated peptides were observed in all the in vitro translated mutants containing that segment. It is concluded that the membrane topogenesis of P450 3A1 is determined mainly by the amino-terminal hydrophobic segment. Birkhäuser Verlag, 1996 Cytochrome P450 nationallicence membrane topology nationallicence endoplasmic reticulum nationallicence in vitro translation nationallicence rat liver nationallicence Van den Broek P. Department of Biochemistry, Gulbenkian Institute of Science, Apartado 14, 2781, Oeiras Codex, (Portugal) aut Barroso M. Department of Biochemistry, Gulbenkian Institute of Science, Apartado 14, 2781, Oeiras Codex, (Portugal) aut Lechner M. Department of Biochemistry, Gulbenkian Institute of Science, Apartado 14, 2781, Oeiras Codex, (Portugal) aut Experientia Birkhäuser-Verlag 52/9(1996-09-01), 851-855 0014-4754 52:9<851 1996 52 18 https://doi.org/10.1007/BF01938869 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01938869 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Van den Broek P. Department of Biochemistry, Gulbenkian Institute of Science, Apartado 14, 2781, Oeiras Codex, (Portugal) aut NATIONALLICENCE 700 1- Barroso M. Department of Biochemistry, Gulbenkian Institute of Science, Apartado 14, 2781, Oeiras Codex, (Portugal) aut NATIONALLICENCE 700 1- Lechner M. Department of Biochemistry, Gulbenkian Institute of Science, Apartado 14, 2781, Oeiras Codex, (Portugal) aut NATIONALLICENCE 773 0- Experientia Birkhäuser-Verlag 52/9(1996-09-01), 851-855 0014-4754 52:9<851 1996 52 18 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer