Functions of signal and signal-anchor sequences are determined by the balance between the hydrophobic segment and the N-terminal charge

摘要: The signal sequence of secretory proteins and the signal-anchor type II membrane initiate translocation following polypeptide segments, whereas cytochrome P-450-type mediates insertion via a signal-recognition particle-dependent mechanism but does not lead to C-terminal sequences. To establish structural requirements for function sequences, we constructed chimeric containing artificial topogenic sequences in which N-terminal net charge length hydrophobic segment were systematically altered. Utilizing an vitro translation-translocation system, found that segments consisting 7-10 leucine residues functioned as with 12-15 showed different functions, behaving or depending on charge. From these observations, propose depends balance between segment.