| molecular function |
|---|
| | GO:0008312 | | 7S RNA binding | | Interacting selectively and non-covalently with 7S RNA, the RNA component of the signal recognition particle (SRP). |
| | GO:0003723 | | RNA binding | | Interacting selectively and non-covalently with an RNA molecule or a portion thereof. |
| | GO:0030942 | | endoplasmic reticulum signal peptide binding | | Interacting selectively and non-covalently with an endoplasmic reticulum signal peptide, a specific peptide sequence that acts as a signal to localize the protein within the endoplasmic reticulum. |
| biological process |
|---|
| | GO:0006614 | | SRP-dependent cotranslational protein targeting to membrane | | The targeting of proteins to a membrane that occurs during translation and is dependent upon two key components, the signal-recognition particle (SRP) and the SRP receptor. SRP is a cytosolic particle that transiently binds to the endoplasmic reticulum (ER) signal sequence in a nascent protein, to the large ribosomal unit, and to the SRP receptor in the ER membrane. |
| | GO:0006617 | | SRP-dependent cotranslational protein targeting to membrane, signal sequence recognition | | The process in which SRP binds to the signal peptide in a nascent protein, causing protein elongation to pause, during cotranslational membrane targeting. |
| | GO:0045047 | | protein targeting to ER | | The process of directing proteins towards the endoplasmic reticulum (ER) using signals contained within the protein. One common mechanism uses a 16- to 30-residue signal sequence, typically located at the N-terminus of the protein and containing positively charged amino acids followed by a continuous stretch of hydrophobic residues, which directs the ribosome to the ER membrane and initiates transport of the growing polypeptide across the ER membrane. |
| cellular component |
|---|
| | GO:0005737 | | cytoplasm | | All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures. |
| | GO:0030529 | | intracellular ribonucleoprotein complex | | An intracellular macromolecular complex containing both protein and RNA molecules. |
| | GO:0005730 | | nucleolus | | A small, dense body one or more of which are present in the nucleus of eukaryotic cells. It is rich in RNA and protein, is not bounded by a limiting membrane, and is not seen during mitosis. Its prime function is the transcription of the nucleolar DNA into 45S ribosomal-precursor RNA, the processing of this RNA into 5.8S, 18S, and 28S components of ribosomal RNA, and the association of these components with 5S RNA and proteins synthesized outside the nucleolus. This association results in the formation of ribonucleoprotein precursors; these pass into the cytoplasm and mature into the 40S and 60S subunits of the ribosome. |
| | GO:0005634 | | nucleus | | A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent. |
| | GO:0048500 | | signal recognition particle | | A complex of protein and RNA which facilitates translocation of proteins across membranes. |
| | GO:0005786 | | signal recognition particle, endoplasmic reticulum targeting | | A ribonucleoprotein particle of 325 kDa composed of a 7S (300 nucleotide) RNA molecule and a complex of six different polypeptides. This binds both to the N-terminal signal peptide for proteins destined for the endoplasmic reticulum as they emerge from the large ribosomal subunit and also to the ribosome. This binding arrests further translation thereby preventing the proteins from being released into the cytosol. The SRP-ribosome complex then diffuses to the endoplasmic reticulum where it is bound to the signal recognition particle receptor, which allows resumption of protein synthesis and facilitates the passage of the growing polypeptide chain through the translocon. Through a process involving GTP hydrolysis, the SRP-SRP receptor complex dissociates and SRP returns to the cytosol. Of the six polypeptides of SRP the 54 kDa subunit (SRP54) is the central player. It contains an N-terminal GTPase domain and a C-terminal domain that binds directly to the signal peptide and the SRP RNA. Examples of this component are found in Mus musculus, Saccharomyces cerevisiae and Arabidopsis thaliana. |
Description
