untitled

Vesicle trafficking

Endocytosis

Exocytosis

SSPK

SPK

ER G

M

V

E

Membrane

Cell wall

Fig. 3.18Hypothetical model of the organization of the vesicle-trafficking network in a growing hypha, based on
the pattern of FM4-64 staining. E =endosome; ER =endoplasmic reticulum; G =Golgi cisterna; M =mitochondrion;
SPK =Spitzenkörper; SSPK =satellite Spitzenkörper; V =vacuole. (From Fisher-Parton et al. 2000.)

Fig. 3.19Young (3 hour) germlings from a uredospore (Us) of the rust fungus Uromyces phaseoli, treated with differ-

ent compounds to reveal the distribution of hyphal components. Scale bars = 10 μm. (Image 1) Treated with DAPI, a

compound that binds to A/ T-rich regions of DNA, and observed by a combination of phase-contrast and fluorescence

microscopy. The two nuclei (N) in the germ-tube are seen by DAPI fluorescence. (Image 2) The same germling treated

with fluorochrome-labeled, anti-tubulin antibodies and observed by fluorescence microscopy. The many microtubules

that run longitudinally in the hypha are clearly seen. (Image 3) The same germling observed by fluorescence micro-

scopy but treated with rhodamine-conjugated phalloin (a deadly toxin from toadstools of the “death cap” fungus Amanita

phalloideswhich exerts its effects by binding to actin). A conspicuous actin cap is seen in the hyphal tip. Actin is also

seen as peripheral plaques (p) and nuclear inclusions (ni) in zones similar to those in which microtubules are seen.

(Courtesy of H.C. Hoch; from Hoch & Staples 1985.)