Related Experiment Video

Updated: May 30, 2026

Expression of Fluorescent Proteins in Branchiostoma lanceolatum by mRNA Injection into Unfertilized Oocytes
09:31

Expression of Fluorescent Proteins in Branchiostoma lanceolatum by mRNA Injection into Unfertilized Oocytes

Published on: January 12, 2015

Alternative gene expression in type I and type II cells may enable further nuclear changes during conjugation of

Mayumi Sugiura1, Yuri Tanaka, Toshinobu Suzaki

  • 1Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan.

Protist
|August 16, 2011
PubMed

Insights

In Blepharisma, specific gene expression in mating-type II cells, not type I, is crucial for initiating conjugation. Gene expression patterns in heterotypic pairs differ from homotypic pairs, suggesting a trigger for nuclear changes like meiosis.

Area of Science:

  • Cell Biology
  • Genetics
  • Protozoology

Background:

  • Most ciliates undergo meiosis and nuclear changes during conjugation in homotypic pairs.
  • In Blepharisma, conjugation occurs only in heterotypic pairs, with homotypic pairs lacking a trigger for nuclear changes.
  • Previous studies identified BjCdk1, Bj4HPPD, and BjCks genes upregulated in gamone1-treated type II cells.

Purpose of the Study:

  • To investigate the molecular structures and expression patterns of BjCdk1, Bj4HPPD, and BjCks.
  • To compare gene expression in homotypic and heterotypic pairs during Blepharisma conjugation.
  • To explore the potential trigger for initiating nuclear changes and meiosis in Blepharisma conjugation.

Main Methods:

  • Gene expression analysis of BjCdk1, Bj4HPPD, and BjCks in type I and type II Blepharisma cells.
  • Quantitative comparison of these gene expressions in homotypic and heterotypic pairs over time.
  • Investigating molecular structures of the identified genes.

Main Results:

  • BjCdk1, Bj4HPPD, and BjCks were specifically expressed in gamone1-treated type II cells, but not in gamone2-treated type I cells.
  • In heterotypic pairs, gene expression remained stable or decreased gradually during conjugation.
  • In homotypic pairs, expression of these genes rapidly decreased and ceased after 10 hours.

Conclusions:

  • Gene expression in Blepharisma conjugation is mating-type specific.
  • Alternative gene expression in mating types I and II, along with factor merging in heterotypic pairs, likely induces nuclear changes, including meiosis.
  • These findings provide insights into the regulatory mechanisms of ciliate conjugation.

More Related Videos

Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation10:41

Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation

Published on: January 4, 2017

Transient Expression and Cellular Localization of Recombinant Proteins in Cultured Insect Cells12:09

Transient Expression and Cellular Localization of Recombinant Proteins in Cultured Insect Cells

Published on: April 20, 2017

Related Concept Videos

Exon Recombination02:32

Exon Recombination

The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes. 
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Methods of Nuclear Reprogramming01:24

Methods of Nuclear Reprogramming

Nuclear reprogramming is a process of transforming one cell type into an unrelated cell type by epigenetic changes that alter the cell’s original gene expression pattern. Such epigenetic changes force cells to express a different set of genes, which play a significant role in inducing transformation into other cell types. Nuclear reprogramming offers applications in reproductive cloning for livestock propagation and regenerative medicine — developing patient-specific cells for injury repair.
Yeast Signaling01:28

Yeast Signaling

Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
Position-effect Variegation02:32

Position-effect Variegation

In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
Epistasis Analysis01:09

Epistasis Analysis

Although Mendel chose seven unrelated traits in peas to study gene segregation, most traits involve multiple gene interactions that create a spectrum of phenotypes. When the interaction of various genes or alleles at different locations influences a phenotype, this is called epistasis. Epistasis often involves one gene masking or interfering with the expression of another (antagonistic epistasis). Epistasis often occurs when different genes are part of the same biochemical pathway. The...
Chromatin Modification in iPS Cells01:32

Chromatin Modification in iPS Cells

Chromatin modification alters gene expression; therefore, scientists can add histone-modifying enzymes, histone variants, and chromatin remodeling complexes to somatic cells to aid reprogramming into pluripotent stem (iPS) cells.
Compact chromatin makes reprogramming difficult. Enzymes, such as histone demethylases and acetyltransferases, are often added during reprogramming to loosen the chromatin, making the DNA more accessible to transcription factors. Molecules that inhibit histone...