The peroxisome protein translocation machinery is developmentally regulated in the fungus .

Sexual reproduction allows eukaryotic organisms to produce genetically diverse progeny. This process relies on meiosis, a reductional division that enables ploidy maintenance and genetic recombination. Meiotic differentiation also involves the renewal of cell functioning to promote offspring rejuvenation.

Spatiotemporal Dynamic Regulation of Organelles During Meiotic Development, Insights From Fungi.

Eukaryotic cell development involves precise regulation of organelle activity and dynamics, which adapt the cell architecture and metabolism to the changing developmental requirements. Research in various fungal model organisms has disclosed that meiotic development involves precise spatiotemporal regulation of the formation and dynamics of distinct intracellular membrane compartments, including peroxisomes, mitochondria and distinct domains of the endoplasmic reticulum, comprising its peripheral domains and the nuclear envelope. This developmental regulation implicates changes in the constitution and dynamics of these organelles, which modulate their structure, abundance and distribution.

Spindle Dynamics during Meiotic Development of the Fungus Podospora anserina Requires the Endoplasmic Reticulum-Shaping Protein RTN1.

The endoplasmic reticulum (ER) is an elaborate organelle composed of distinct structural and functional domains. ER structure and dynamics involve membrane-shaping proteins of the reticulon and Yop1/DP1 families, which promote membrane curvature and regulate ER shaping and remodeling. Here, we analyzed the function of the reticulon (RTN1) and Yop1 proteins (YOP1 and YOP2) of the model fungus Podospora anserina and their contribution to sexual development.

The taxonomy of the model filamentous fungus .

The filamentous fungus has been used as a model organism for more than 100 years and has proved to be an invaluable resource in numerous areas of research. Throughout this period, has been embroiled in a number of taxonomic controversies regarding the proper name under which it should be called. The most recent taxonomic treatment proposed to change the name of this important species to .

Distinct Contributions of the Peroxisome-Mitochondria Fission Machinery During Sexual Development of the Fungus .

Mitochondria and peroxisomes are organelles whose activity is intimately associated and that play fundamental roles in development. In the model fungus , peroxisomes and mitochondria are required for different stages of sexual development, and evidence indicates that their activity in this process is interrelated. Additionally, sexual development involves precise regulation of peroxisome assembly and dynamics.

An endoplasmic reticulum domain is associated with the polarized growing cells of Podospora anserina hyphae.

The endoplasmic reticulum (ER) is composed of distinct structural domains that perform diverse essential functions, including the synthesis of membrane lipids and proteins of the cell endomembrane system. The polarized growth of fungal hyphal cells depends on a polarized secretory system, which delivers vesicles to the hyphal apex for localized cell expansion, and that involves a polarized distribution of the secretory compartments, including the ER. Here we show that, additionally, the ER of the ascomycete Podospora anserina possesses a peripheral ER domain consisting of highly dynamic pleomorphic ER sub-compartments, which are specifically associated with the polarized growing apical hyphal cells.

NADPH Oxidase NOX-1 Is Localized in the Vacuolar System and the Plasma Membrane.

The NADPH oxidases (NOX) catalyze the production of superoxide by transferring electrons from NADPH to O, in a regulated manner. In NOX-1 is required for normal growth of hyphae, development of aerial mycelium and asexual spores, and it is essential for sexual differentiation and cell-cell fusion. Determining the subcellular localization of NOX-1 is a critical step in understanding the mechanisms by which this enzyme can regulate all these different processes.

Meiotic development initiation in the fungus Podospora anserina requires the peroxisome receptor export machinery.

Peroxisomes are versatile organelles essential for diverse developmental processes. One such process is the meiotic development of Podospora anserina. In this fungus, absence of the docking peroxin PEX13, the RING-finger complex peroxins, or the PTS2 co-receptor PEX20 blocks sexual development before meiocyte formation.

Peroxisome dynamics during development of the fungus Podospora anserina.

Peroxisomes are versatile and dynamic organelles that are required for the development of diverse eukaryotic organisms. We demonstrated previously that in the fungus Podospora anserina different peroxisomal functions are required at distinct stages of sexual development, including the initiation and progression of meiocyte (ascus) development and the differentiation and germination of sexual spores (ascospores). Peroxisome assembly during these processes relies on the differential activity of the protein machinery that drives the import of proteins into the organelle, indicating a complex developmental regulation of peroxisome formation and activity.

Peroxisomes and sexual development in fungi.

Peroxisomes are versatile and dynamic organelles that are essential for the development of most eukaryotic organisms. In fungi, many developmental processes, such as sexual development, require the activity of peroxisomes. Sexual reproduction in fungi involves the formation of meiotic-derived sexual spores, often takes place inside multicellular fruiting bodies and requires precise coordination between the differentiation of multiple cell types and the progression of karyogamy and meiosis.

A network of HMG-box transcription factors regulates sexual cycle in the fungus Podospora anserina.

High-mobility group (HMG) B proteins are eukaryotic DNA-binding proteins characterized by the HMG-box functional motif. These transcription factors play a pivotal role in global genomic functions and in the control of genes involved in specific developmental or metabolic pathways. The filamentous ascomycete Podospora anserina contains 12 HMG-box genes.

Rad53 is essential for a mitochondrial DNA inheritance checkpoint regulating G1 to S progression.

The Chk2-mediated deoxyribonucleic acid (DNA) damage checkpoint pathway is important for mitochondrial DNA (mtDNA) maintenance. We show in this paper that mtDNA itself affects cell cycle progression. Saccharomyces cerevisiae rho(0) cells, which lack mtDNA, were defective in G1- to S-phase progression.

The importomer peroxins are differentially required for peroxisome assembly and meiotic development in Podospora anserina: insights into a new peroxisome import pathway.

Peroxisome biogenesis relies on two known peroxisome matrix protein import pathways that are mediated by the receptors PEX5 and PEX7. These pathways converge at the importomer, a peroxisome-membrane complex that is required for protein translocation into peroxisomes and consists of docking and RING-finger subcomplexes. In the fungus Podospora anserina, the RING-finger peroxins are crucial for meiocyte formation, while PEX5, PEX7 or the docking peroxin PEX14 are not.

Mitochondrial manoeuvres: latest insights and hypotheses on mitochondrial partitioning during mitosis in Saccharomyces cerevisiae.

Movement and positional control of mitochondria and other organelles are coordinated with cell cycle progression in the budding yeast, Saccharomyces cerevisiae. Recent studies have revealed a checkpoint that inhibits cytokinesis when there are severe defects in mitochondrial inheritance. An established checkpoint signaling pathway, the mitotic exit network (MEN), participates in this process.

The peroxisome RING-finger complex is required for meiocyte formation in the fungus Podospora anserina.

Peroxisomes are involved in a variety of metabolic pathways and developmental processes. In the filamentous fungus Podospora anserina, absence of different peroxins implicated in peroxisome matrix protein import leads to different developmental defects. Lack of the RING-finger complex peroxin PEX2 blocks sexual development at the dikaryotic stage, while in absence of both receptors, PEX5 and PEX7, karyogamy and meiosis can proceed and sexual spores are formed.