Biology:Spitzenkörper
The Spitzenkörper (German for 'pointed body', SPK) is a structure found in fungal hyphae that 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 in fungi.[1]
The vesicles are organized around a central area that contains a dense meshwork of microfilaments. Polysomes are often found closely to the posterior boundary of the Spitzenkörper core within the Ascomycota, microtubules extend into and often through the Spitzenkörper and within the Ascomycota Woronin bodies are found in the apical region near the Spitzenkörper.[2]
The cytoplasm of the extreme apex is occupied almost exclusively by secretory vesicles. In the higher fungi (Ascomycota and Basidiomycota), secretory vesicles are arranged into a dense, spherical aggregation called the Spitzenkörper or ‘apical body’. The Spitzenkörper may be seen in growing hyphae even with a light microscope. Hyphae of the Oomycota and some lower Eumycota (notably the Zygomycota) do not contain a recognizable Spitzenkörper, and the vesicles are instead distributed more loosely often in a crescent-shaped arrangement beneath the apical plasma membrane.[3]
This structure is most commonly found in Dikarya and was at first thought to only occur among them.[4][5][6][7][8] Vargas et al 1993 however were the first to find a Spitzenkörper in another clade, specifically the Allomyces (Blastocladiomycota),[5][9][6][4][7][8] then subsequently Basidiobolus ranarum – which has been placed in several different phyla – was also found to have an SPK.[4] (As of 2020) these and the Blastocladiella (also in Blastocladiomycota) are the only known taxa to bear this structure.[8]
References
- ↑ Steinberg, G. (2007). "Hyphal growth: a tale of motors, lipids, and the Spitzenkörper". Eukaryotic Cell 6 (3): 351–360. doi:10.1128/EC.00381-06. PMID 17259546.
- ↑ Harris, S.; Read, N.; Roberson, R.; Shaw, B.; Seiler, S.; Plamann, M.; Momany, M. (2005). "Polarisome meets spitzenkörper: microscopy, genetics, and genomics converge". Eukaryotic Cell 4 (2): 225–229. doi:10.1128/EC.4.2.225-229.2005. PMID 15701784.
- ↑ Webster, John; Weber, R. W. S. (2007). Introduction to Fungi (Third ed.). New York: Cambridge University Press. ISBN 978-0-521-80739-5.
- ↑ 4.0 4.1 4.2 Steinberg, Gero; Peñalva, Miguel A.; Riquelme, Meritxell; Wösten, Han A.; Harris, Steven D. (2017-03-10). Heitman, Joseph. ed. "Cell Biology of Hyphal Growth". Microbiology Spectrum (American Society for Microbiology) 5 (2): 1–34. doi:10.1128/microbiolspec.funk-0034-2016. ISSN 2165-0497. PMID 28429675.
- ↑ 5.0 5.1 Powell, Martha J.; Letcher, Peter M. (2014). "Chytridiomycota, Monoblepharidomycota, and Neocallimastigomycota". Systematics and Evolution. 7A (2 ed.). Berlin: Springer. pp. 141–175. ISBN 978-3-642-55318-9. OCLC 889948520. ISBN:978-3-642-55317-2.
- ↑ 6.0 6.1 Richards, Thomas A.; Leonard, Guy; Wideman, Jeremy G. (2017-05-19). "What Defines the "Kingdom" Fungi?". Microbiology Spectrum (American Society for Microbiology) 5 (3): 55–77. doi:10.1128/microbiolspec.funk-0044-2017. ISSN 2165-0497. PMID 28643626.
- ↑ 7.0 7.1 Naranjo‐Ortiz, Miguel A.; Gabaldón, Toni (2019-04-25). "Fungal evolution: major ecological adaptations and evolutionary transitions". Biological Reviews of the Cambridge Philosophical Society (Cambridge Philosophical Society (Wiley)) 94 (4): 1443–1476. doi:10.1111/brv.12510. ISSN 1464-7931. PMID 31021528.
- ↑ 8.0 8.1 8.2 Naranjo‐Ortiz, Miguel A.; Gabaldón, Toni (2020-04-17). "Fungal evolution: cellular, genomic and metabolic complexity". Biological Reviews of the Cambridge Philosophical Society (Cambridge Philosophical Society (Wiley)) 95 (5): 1198–1232. doi:10.1111/brv.12605. ISSN 1464-7931. PMID 32301582.
- ↑ Berbee, Mary L.; James, Timothy Y.; Strullu-Derrien, Christine (2017-09-08). "Early Diverging Fungi: Diversity and Impact at the Dawn of Terrestrial Life". Annual Review of Microbiology (Annual Reviews) 71 (1): 41–60. doi:10.1146/annurev-micro-030117-020324. ISSN 0066-4227. PMID 28525299.
 |  |
