LIS - Legume Information System
Information about legume traits for crop improvement
GlycineMine
v5.1.0.3
Glycine data from LIS
v5.1.0.3
Glycine data from LIS
| Type | Family |
| Description | Translocation of polypeptide chains across the endoplasmic reticulum (ER) membrane is triggered by signal sequences. Subsequently, signal recognition particle interacts with its membrane receptor and the ribosome-bound nascent chain is targeted to the ER where it is transferred into a protein-conducting channel. At some point, a second signal sequence recognition event takes place in the membrane and translocation of the nascent chain through the membrane occurs. The signal sequence of most secretory and membrane proteins is cleaved off at this stage. Cleavage occurs by the signal peptidase complex (SPC) as soon as the lumenal domain of the translocating polypeptide is large enough to expose its cleavage site to the enzyme. The signal peptidase complex is possibly also involved in proteolytic events in the ER membrane other than the processing of the signal sequence, for example the further digestion of the cleaved signal peptide or the degradation of membrane proteins [ ]. This family represents the Signal peptidase complex subunit 1 (SPCS1) and its homologues, such as Spc1 from budding yeasts. The signal peptidase complex cleaves the signal sequence from proteins targeted to the endoplasmic reticulum (ER). Mammalian signal peptidase is as a complex of five different polypeptide chains [ ], while the budding yeast SPC comprises four proteins []. Budding yeast Spc1 has been shown to be a nonessential component of the signal peptidase complex []. However, the Drosophila spase12 (yeast Spc1 homologue) null alleles are embryonic lethal [].Interestingly, human SPC12 has been linked to post-translational processing of proteins involved in virion assembly and secretion from flaviviruses [ , , ]. Signal peptidase complex-like protein DTM1 from Oryza sativa (rice) also belongs to this family. This protein unctions in tapetum development during early meiosis. It may play a role in the endoplasmic reticulum (ER) membrane in the early stages of tapetum development in anthers [ ]. |
| Short Name | Spc1/SPCS1 |
