Spitzenkörper
Encyclopedia
The Spitzenkörper is a structure found in fungal hyphae which is the organizing center for hyphal growth and morphogenesis
. It consists of many small vesicles
and is present in growing hyphal tips, during spore germination and where branch formation occurs. Its position in the hyphal tip correlates with the direction of hyphal growth. The spitzenkörper is a part of the endomembrane system
system in fungi.
The vesicles are organized around a central area that contains a dense meshwork of microfilament
s. Polysome
s are often found closely to the posterior boundary of the Spitzenkörper core, microtubules extend into and often through the Spitzenkörper and Woronin bodies
are found in the apical region near the Spitzenkörper.
The cytoplasm of the extreme apex is occupied almost exclusively by secretory vesicles and microvesicles. In the higher fungi (Asco- and Basidiomycota), the former are arranged as a spherical shell around the latter, and the entire formation is called the Spitzenkorper or ‘apical body’. The Spitzenkorper may be seen in growing hyphae even with the light microscope. Hyphae of the Oomycota and some lower Eumycota (notably the Zygomycota) do not contain a recognizable Spitzenkorper, and the vesicles are instead distributed more loosely in the apical dome.
Morphogenesis
Morphogenesis , is the biological process that causes an organism to develop its shape...
. It consists of many small vesicles
Vesicle (biology)
A vesicle is a bubble of liquid within another liquid, a supramolecular assembly made up of many different molecules. More technically, a vesicle is a small membrane-enclosed sack that can store or transport substances. Vesicles can form naturally because of the properties of lipid membranes , or...
and is present in growing hyphal tips, during spore germination and where branch formation occurs. Its position in the hyphal tip correlates with the direction of hyphal growth. The spitzenkörper is a part of the endomembrane system
Endomembrane system
The endomembrane system is composed of the different membranes that are suspended in the cytoplasm within a eukaryotic cell. These membranes divide the cell into functional and structural compartments, or organelles...
system in fungi.
The vesicles are organized around a central area that contains a dense meshwork of microfilament
Microfilament
Microfilaments are the thinnest filaments of the cytoskeleton, a structure found in the cytoplasm of all eukaryotic cells. These linear polymers of actin subunits are flexible and relatively strong, resisting buckling by multi-piconewton compressive forces and filament fracture by nanonewton...
s. Polysome
Polysome
Polyribosomes also known as ergosomes are a cluster of ribosomes, bound to a mRNA molecule, first discovered and characterized by Jonathan Warner, Paul Knopf, and Alex Rich in 1963. Many ribosomes read one mRNA simultaneously, progressing along the mRNA to synthesize the same protein...
s are often found closely to the posterior boundary of the Spitzenkörper core, microtubules extend into and often through the Spitzenkörper and Woronin bodies
Woronin body
A Woronin body is a peroxisome-derived, dense core microbody with a double membrane found near the septae that divide hyphal compartments in filamentous Ascomycota. One established function of Woronin bodies is the plugging of the septal pores after hyphal wounding, which restricts theloss of...
are found in the apical region near the Spitzenkörper.
The cytoplasm of the extreme apex is occupied almost exclusively by secretory vesicles and microvesicles. In the higher fungi (Asco- and Basidiomycota), the former are arranged as a spherical shell around the latter, and the entire formation is called the Spitzenkorper or ‘apical body’. The Spitzenkorper may be seen in growing hyphae even with the light microscope. Hyphae of the Oomycota and some lower Eumycota (notably the Zygomycota) do not contain a recognizable Spitzenkorper, and the vesicles are instead distributed more loosely in the apical dome.