Biochemical and physiological properties of a protein inducing protoplast release during conjugation in theClosterium peracerosum-strigosum-littorale complex

  title={Biochemical and physiological properties of a protein inducing protoplast release during conjugation in theClosterium peracerosum-strigosum-littorale complex},
  author={Hiroyuki Sekimoto and Shinobu Satoh and Tadashi Fujii},
When mating-type minus (mt−) and plus (mt+) cells of theClosterium peracerosum-strigosum-littorale complex were mixed together in a nitrogen-deficient mating medium, cells of both types released protoplasts, this release being the first step in the process of conjugation. Release of protoplasts by mt− cells also proceeded without pairing in a medium in which mt− and mt+ cells had previously been cultured together. A protein with the ability to induce the release of protoplasts was purified from… 
Analysis of binding of biotinylated protoplast-release-inducing protein that induces release of gametic protoplasts in the Closterium peracerosum-strigosum-littorale complex
It appears that the PR-IP induces the release of protoplasts from mt− cells by binding of a polypeptide of relative molecular mass 19000 to the receptor on the cell surface in a manner analogous to the binding of peptide hormones in animals.
Regulation of expression of the genes for a sex pheromone by an inducer of the sex pheromone in the Closterium peracerosum-strigosum-littorale complex
It is suggested that PR-IP is synthesized de novo and secreted from mt+ cells only after the perception of PRIP Inducer that has been released from mt− cells in the light during the sexual reproduction of Closterium.
Characterization and molecular cloning of conjugation-regulating sex pheromones in homothallic Closterium.
Results indicate that conjugation of the homothallic strain is regulated by an ortholog of a heterothallic sex-specific pheromone, and Recombinant PR-IP Inducers produced by yeast cells showed conjugated-promoting activity.
Physiological characterization of the sex pheromone protoplast‐release‐inducing protein from the Closterium peracerosum‐strigosum‐littorale complex (Charophyta)
Results strongly suggest that PR‐IP is a multifunctional pheromone that independently promotes multiple steps in conjugation at the appropriate times through different induction mechanisms.
CRISPR/Cas9-based knockouts reveal that CpRLP1 is a negative regulator of the sex pheromone PR-IP in the Closterium peracerosum-strigosum-littorale complex
It is concluded that CpRLP1 is a negative regulator of PR-IP that regulates the timing of protoplast release in conjugating C. psl.
Concanavalin A Disrupts the Release of Fibrous Material Necessary for Zygote Formation of a Unicellular Charophycean Alga, Closterium peracerosum-strigosum-littorale Complex
It is suggested that an unknown molecule(s) recognized by Con A is essential for the diffusion of fibrous materials at the conjugation papillae, which is an indispensable step for gamete release during conjugations of the C. psl.
Properties of cell surface carbohydrates in sexual reproduction of the Closterium peracerosum–strigosum–littorale complex (Zygnematophyceae, Charophyta)
Examination of the properties of cell surface carbohydrates in vegetative and reproductive cells using a variety of fluorescein isothiocyanate labeled lectins as probes suggests that different carbohydrates specifically recognized by these lectins are involved in cell recognition and/or fusion during conjugation processes in the C. psl.
A sex pheromone, protoplast release-inducing protein (PR-IP) inducer, induces sexual cell division and production of PR-IP in Closterium.
The sex pheromone protoplast release-inducing protein (PR-IP) inducer has both PR-IP-inducing and SCD-inducing activities with mt+ cells, although the inducing mechanisms of the two phersomones differ.
Detailed analyses on the parthenospore formation in Closterium moniliferum (Zygnematophyceae, Charophyta)
Insight is provided into the mechanisms of cell–cell interactions in parthenosporic strains and the evolution of conjugation styles and the presence of a parthenospore formation-promoting factor.


Sexual Interaction in Heterothallic Strains of Closterium peracerosum-strigosum-littorale: Partial Characterization of a Male-Specific Sexual Pheromone, Protoplast-Releasing Substance.
The results suggest that PRS is a glycoprotein with pronase-sensitive and trypsin-insensitive structure that activates mating type plus cells and results in the release and fusion of protoplasts within distended conjugation-papilla in paired cells.
Biochemical studies on lysin, a cell wall degrading enzyme released during fertilization in Chlamydomonas.
Regulated secretion of a serine protease that activates an extracellular matrix-degrading metalloprotease during fertilization in Chlamydomonas
This work shows that conversion of prolysin to lysin is due to a cellular, nonperiplasmic enzyme that has the properties of a serine protease that is induced by incubation of gametes in dibutyryl cAMP.
Cell-wall lytic enzymes (autolysins) of Chlamydomonas reinhardtii are (hydroxy)proline-specific proteases.
Two stage specific cell-wall lytic enzymes (autolysins) from different strains of the unicellular, biflagellated green alga Chlamydomonas reinhardtii were isolated and purified to homogeneity.
Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4
Using an improved method of gel electrophoresis, many hitherto unknown proteins have been found in bacteriophage T4 and some of these have been identified with specific gene products. Four major
Improved sensitivity for detection and quantitation of glycoproteins on polyacrylamide gels
As compared to other PAS staining methods, this procedure offers a remarkably improved sensitivity for detection and quantitation of glycoproteins following their electrophoretic separation on polyacrylamide gels.