Related Experiment Video
Updated: Jul 19, 2026
05:34
Sexual Crosses with the Mucoromycete Phycomyces blakesleeanus
Published on: June 6, 2025
Mucor rouxii ultrastructure: cyclic AMP and actin cytoskeleton
E Pereyra1, M Ingerfeld, N Anderson
1Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina. epereyra@qb.fcen.uba.ar
Protoplasma
|September 20, 2006
Summary
Dibutyryl-cyclic-AMP (dbcAMP) and latrunculin B disrupt polarized growth in Mucor rouxii, causing reversible changes in cell shape and surface. These compounds affect the actin cytoskeleton, impacting fungal morphology.
Area of Science:
- Mycology
- Cell Biology
- Biochemistry
Background:
- Mucor rouxii is a dimorphic fungus with distinct growth patterns.
- Understanding factors controlling fungal morphogenesis is crucial for controlling growth.
Purpose of the Study:
- To investigate the effects of dibutyryl-cyclic-AMP (dbcAMP) and latrunculin B on Mucor rouxii morphology and ultrastructure.
- To elucidate the roles of protein kinase A and actin cytoskeleton in fungal growth regulation.
Main Methods:
- Comparative analysis of dbcAMP and latrunculin B effects on M. rouxii.
- Light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) for morphological and ultrastructural analysis.
- F-actin staining using fluorescein isothiocyanate-phalloidin.
Main Results:
- Both dbcAMP and latrunculin B induced a switch from polarized to isodiametric growth, which was reversible.
- SEM revealed a change from rough to smooth cell surfaces upon repolarization.
- TEM showed enlarged cell walls with irregular depositions and detachment from the cell membrane.
- dbcAMP-treated cells had fewer glycogen granules; F-actin staining indicated reduced fluorescence in treated cells.
Conclusions:
- Sustained activation of protein kinase A by dbcAMP impairs polarized growth, likely via actin cytoskeleton modification.
- Latrunculin B's disruption of the actin cytoskeleton also affects cell morphology.
- Results suggest a potential involvement of an integrin-like pathway in dbcAMP-induced effects on cell adhesion and wall structure.
More Related Videos
Related Concept Videos
02:15The Contractile Ring
Contractile rings are composed of microfilaments and are responsible for separating the daughter cells during cytokinesis. Contractile ring assembly proceeds along with other cell cycle events; however, very few mechanistic details are known about the timing and coordination of the contractile rings with the cell cycle.
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
02:15The Contractile Ring
Contractile rings are composed of microfilaments and are responsible for separating the daughter cells during cytokinesis. Contractile ring assembly proceeds along with other cell cycle events; however, very few mechanistic details are known about the timing and coordination of the contractile rings with the cell cycle.
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
01:16Cell Motility through Blebbing
Blebs are a type of membrane protrusion formed by the internal hydrostatic pressure of the cytoplasm. Blebs are observed in several cell types, including fibroblasts, immune cells, and single-celled organisms like the amoeba. The primary function of blebs is cell locomotion and apoptosis, but they are also found during necrosis and cell division. The life cycle of a bleb comprises an initiation phase followed by the expansion and retraction phases.
Blebbing Through the Matrix
In multicellular...
Blebbing Through the Matrix
In multicellular...
01:10The Role of Actin and Myosin in Non-muscle Cells
Actin and myosin or actomyosin filaments also play a significant role in cells other than those involved in muscle contraction (which occurs within the sarcomere of muscle cells). The mechanism of non-muscle cell contractile bundles was first observed in Dictyostelium and Acanthamoeba. In non-muscle cells, two bundles are commonly found: stress fibers and actomyosin adherence belts. These contractile bundles are smaller and less organized than the ones found in muscle cells. They are held...
01:02Role of Microtubules in Cell Wall Deposition
Microtubules are small hollow tubes in eukaryotic cells. The cell wall microtubules are polymerized dimers of two globular proteins, α-tubulin and β-tubulin, two globular proteins. With a diameter of about 25 nm, microtubules are the widest components of the cytoskeleton. They help the cell resist compression and provide a track along which vesicles move through the cell or pull replicated chromosomes to opposite ends of a dividing cell. Microtubules go through quick cycles of disassembly and...
01:18Assembly of Cytoskeletal Filaments
Cytoskeletal filaments are polymeric forms of smaller protein subunits. However, individual cytoskeletal filaments may easily disassemble or associate with other similar filaments to form rigid structures. Microfilaments, made of actin monomers, rely on actin-binding proteins to form bundles and create networks of individual actin filaments. Microtubules rely on microtubule-associated proteins (MAPs) to form sturdy cylindrical structures. However, the proteins involved in forming complex...