Related Experiment Video

Updated: Jul 25, 2025

Genotyping Single Nucleotide Polymorphisms in the Mitochondrial Genome by Pyrosequencing
07:24

Genotyping Single Nucleotide Polymorphisms in the Mitochondrial Genome by Pyrosequencing

Published on: February 10, 2023

1.5K

Validation of the male-specific ORF of the paternally-transmitted mtDNA in Mytilus edulis as a protein-coding gene

Alizée Debelli1, Laura Kienzle1, Hajar Hosseini Khorami1

  • 1Département de Sciences Biologiques, Université de Montréal, Montréal, QC H3C 3J7, Canada.

Gene
|June 25, 2023
PubMed

Insights

Researchers validated a male-specific protein in Mytilus edulis, encoded by the paternal mitochondrial genome. This protein is found in sperm mitochondria and acrosomes, suggesting a role in sperm function during doubly uniparental inheritance.

Area of Science:

  • Marine biology
  • Mitochondrial genetics
  • Bivalve reproduction

Background:

  • Bivalve species exhibit doubly uniparental mitochondrial inheritance (DI).
  • Sex-specific mitochondrial DNA (mtDNA)-encoded proteins are hypothesized to facilitate transmission of female and male mitogenomes.
  • In Mytilus edulis, the female-specific open reading frame (F-ORF) translation is confirmed, but the male-specific ORF (M-ORF) translation remains unverified.

Purpose of the Study:

  • To validate the male-specific ORF (M-ORF) of the paternal mitogenome in Mytilus edulis as a protein-coding gene.
  • To investigate the presence and localization of the M-ORF protein in M. edulis.

Main Methods:

  • Mitochondrial genome analysis in Mytilus edulis.
  • Protein detection assays in male gonads.
  • Immunofluorescence microscopy for protein localization in sperm.

Main Results:

  • The male-specific ORF (M-ORF) of the paternal mitogenome in Mytilus edulis was validated as a protein-coding gene.
  • The M-ORF protein was detected exclusively in male gonads.
  • The M-ORF protein localized to sperm mitochondria and the acrosome.

Conclusions:

  • The M-ORF protein is a male-specific, mitochondrially encoded protein in Mytilus edulis.
  • The localization of M-ORF protein in sperm suggests its involvement in a critical sperm function.
  • This finding contributes to understanding the mechanisms of doubly uniparental mitochondrial inheritance in bivalves.
Keywords:
BivalviaDoubly Uniparential Inheritance of mtDNAMitochondriaMitochondrial DNAMytilus edulisORFan genes

More Related Videos

A Converging Strategy for the Generation of a Virtually Sequenced cDNA Library from Unreferenced Pacific Oysters12:14

A Converging Strategy for the Generation of a Virtually Sequenced cDNA Library from Unreferenced Pacific Oysters

Published on: June 13, 2019

5.6K
An Integrated Approach for Microprotein Identification and Sequence Analysis09:37

An Integrated Approach for Microprotein Identification and Sequence Analysis

Published on: July 12, 2022

3.5K

Related Concept Videos

Animal Mitochondrial Genetics02:59

Animal Mitochondrial Genetics

Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
7.7K
Porin Insertion in the Outer Mitochondrial Membrane01:12

Porin Insertion in the Outer Mitochondrial Membrane

Porins are beta-barrel proteins translocated to the mitochondrial outer membrane through the TOM complex into the intermembrane space. Porin precursors bind TIM chaperones within the intermembrane space and are guided to the Sorting and Assembly Machinery complex or SAM complex on the outer mitochondrial membrane.
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
3.1K
Translocation of Proteins into the Mitochondria01:19

Translocation of Proteins into the Mitochondria

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
3.2K
Mitochondrial Protein Sorting01:39

Mitochondrial Protein Sorting

Mitochondria are double-membrane organelles of the eukaryotes involved in cellular metabolism, signaling, ATP synthesis, and programmed cell death.  Each of these processes requires specific proteins and enzymes that must be correctly sorted to the right mitochondrial subcompartment for the proper functioning of the organelle.
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
4.4K
The Y Chromosome Determines Maleness02:19

The Y Chromosome Determines Maleness

The Y chromosome is a sex chromosome found in several vertebrates and mammals, including humans. In addition to 22 pairs of autosomes, the human males have one X chromosome and one Y chromosome. In these organisms, the presence or absence of the Y chromosome determines the development of male traits.
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size....
6.7K
Export of Mitochondrial and Chloroplast Genes02:19

Export of Mitochondrial and Chloroplast Genes

A eukaryotic cell can have up to three different types of genetic systems: nuclear, mitochondrial, and chloroplast. During evolution, organelles have exported many genes to the nucleus; this transfer is still ongoing in some plant species. Approximately 18% of the Arabidopsis thaliana nuclear genome is thought to be derived from the chloroplast’s cyanobacterial ancestor, and around 75% of the yeast genome derived from the mitochondria’s bacterial ancestor. This export has occurred...
3.7K