KDEL Retention Signal

Detect a C-terminal KDEL ER retention signal.

Description

A KDEL retention-signal check looks only at the sequence terminus.

A KDEL retention-signal check looks only at the sequence terminus. An internal occurrence does not satisfy this exact terminal comparison.^[1]

Detect a C-terminal KDEL ER retention signal.

When to use KDEL Retention Signal

Use this tool to detect a C-terminal KDEL ER retention signal.

Prepare the canonical sequence, peptide assignments, fitted assay parameters or upstream measurements requested. Keep corresponding entries aligned, use the stated mass and signal units, and remove FASTA headers before entering sequence text.

How to use KDEL Retention Signal and understand its results

Prepare the canonical sequence, peptide assignments, fitted assay parameters or upstream measurements requested. Keep corresponding entries aligned, use the stated mass and signal units, and remove FASTA headers before entering sequence text.
Enter sequence using the field table and calculation rules, then run the tool.
Read retentionMotif, matched. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
sequence	Sequence	string	Required

Enter a canonical sequence. Return the last four residues, or the whole shorter sequence, and exact equality flag.

The shared sequence helper trims outer whitespace and uppercases the sequence. It requires at least one residue from ACDEFGHIKLMNPQRSTVWY. Internal whitespace, FASTA headers, ambiguous letters and modified-residue notation are rejected. Sequence indexes refer to the normalized sequence; individual tools may preserve original strings in their returned lists as explained above.

matched=last four residues equal KDEL

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
retentionMotif	Retention motif	string
matched	Matched	boolean

json

{
  "input": {
    "sequence": "AKDEL"
  },
  "output": {
    "retentionMotif": "KDEL",
    "matched": true
  }
}

Limitations and assumptions

Other retention-signal variants and biological context are not evaluated. A match alone does not establish ER localization.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use PTS1 Terminal Signal: Check a peroxisomal PTS1 terminus against caller-accepted tripeptides. For a complementary task, use GPI Anchor Signal Screen: Screen C-terminal omega site and hydrophobic tail for a GPI-anchor signal.

References

KDEL Retention Signal — tool.io

Similar or alternative tools

PTS1 Terminal Signal
Check a peroxisomal PTS1 terminus against caller-accepted tripeptides.
GPI Anchor Signal Screen
Screen C-terminal omega site and hydrophobic tail for a GPI-anchor signal.