Related Experiment Video

Updated: Jul 28, 2026

Tracking Drug-induced Changes in Receptor Post-internalization Trafficking by Colocalizational Analysis
07:48

Tracking Drug-induced Changes in Receptor Post-internalization Trafficking by Colocalizational Analysis

Published on: July 3, 2015

A delta opioid receptor lacking the third cytoplasmic loop is generated by atypical mRNA processing in human

P Mayer1, H Tischmeyer, M Jayasinghe

  • 1Institute for Pharmacology and Toxicology, Otto von Guericke University of Magdeburg, Germany.

FEBS Letters
|October 18, 2000
PubMed

Insights

Researchers found a shorter delta opioid receptor variant in human melanomas, likely linked to cancer. This variant, absent in healthy cells, suggests a correlation between the altered receptor and malignancy.

Area of Science:

  • Molecular biology
  • Oncology
  • Neuroscience

Background:

  • Delta opioid receptors (DOR) are G protein-coupled receptors involved in various physiological processes.
  • Aberrant receptor expression and function are implicated in cancer development and progression.

Purpose of the Study:

  • To investigate the presence and characteristics of delta opioid receptors in human melanomas.
  • To determine if specific DOR variants are associated with melanoma malignancy.

Main Methods:

  • Reverse transcription polymerase chain reaction (RT-PCR) to detect DOR mRNA.
  • Radioligand binding assays to quantify DORs.
  • Analysis of mRNA processing and splice variants.

Main Results:

  • Delta opioid receptors were identified in human melanomas.
  • A shorter DOR variant, lacking 144 bp from the third exon (third cytoplasmic domain), was consistently detected in all tumors.
  • This variant resulted from atypical mRNA processing, resembling transposon excision, and was absent in normal melanocytes and brain tissue.
  • The short DOR variant was also found in a human neuroblastoma cell line.

Conclusions:

  • The short delta opioid receptor variant appears to be specifically associated with malignancy.
  • Its unique processing suggests a potential role in melanoma development or progression.
  • Further research is warranted to elucidate the functional implications of this variant in cancer.

More Related Videos

Using X-ray Crystallography, Biophysics, and Functional Assays to Determine the Mechanisms Governing T-cell Receptor Recognition of Cancer Antigens09:53

Using X-ray Crystallography, Biophysics, and Functional Assays to Determine the Mechanisms Governing T-cell Receptor Recognition of Cancer Antigens

Published on: February 6, 2017

Tropomodulin 3 Overexpression as a Marker for Platinum Resistance and Immune Infiltration in Ovarian Cancer09:40

Tropomodulin 3 Overexpression as a Marker for Platinum Resistance and Immune Infiltration in Ovarian Cancer

Published on: August 2, 2024

Related Concept Videos

MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
RNA Splicing01:32

RNA Splicing

Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
Nonsense-mediated mRNA Decay02:27

Nonsense-mediated mRNA Decay

The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Receptor Downregulation in MVBs01:15

Receptor Downregulation in MVBs

Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that  lead to cell proliferation, migration, and differentiation. Overexpression of EGFR  stimulates cells to proliferate. Excessive  EGFR activation may...
Export of Misfolded Proteins out of the ER01:32

Export of Misfolded Proteins out of the ER

After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...