Reticulocalbin (RTC)
entry list
alignment
Reticulocalbin (RTC), also known as E6BP (E6 binding protein) or
ERC-55, appears to bind E6, a transforming protein from human
papilloma virus that interacts with tumor suppressor protein p53. RTC
has 210 amino acids [27]. It contains six EF-hands, several of which
are most similar to the corresponding domains of SCF. RTC is inferred
to be in the lumen of the endoplasmic reticulum because it has an
N-terminal leader sequence and a glycosylation site. The C-terminal
sequence is HDEL; this is similar to the KDEL that serves as a signal
to retain proteins within the ER. Four of six EF-hands (1, 4, 5 & 6)
bind calcium but 2 & 3 do not [28].