Kb. Aslanidi et al., INFORMATION-ENERGETIC MODULE AS THE FUNCT IONAL UNIT OF THE NEUROSPORA-CRASSA POLARIZED GROWTH, Biologiceskie membrany, 13(1), 1996, pp. 29-39
Growth features of Neurospora crassa mycelium have been studied. Cutti
ng of the N. crassa hypha into 0.1-1-mm fragments completely arrested
the growth of 0.1-0.3-mm apical fragments. Longer apical fragments con
tinued to grow in the apical direction without any delay. The rate of
the apical fragment elongation was higher than 4 mu m/min. The contras
t to the apical fragments, the basal fragments began to grow after a t
en-minute delay and in the opposite directions simultaneously. The elo
ngation rate of 0.1-0.3-mm basal fragments was 1-3 mu m/min. The elong
ation rates both of the basal and apical fragments increased steadily
in the process of growth and were higher than 5 mu m/min for the fragm
ents of 0.8 mm and longer. The branching patterns were also determined
. The ratio of full hyphal length (including all branches) to the numb
er of tips does not differ for the fragments possessing from 1 to 45 t
ips. In our experiments this ratio (<<hyphal growth unit>>) was always
lesser than the electrical cable space constance characterizing the N
. crassa hyphae (0.7 mm). The combined analysis of the experimental da
ta and theoretical considerations on the electric and energetic interc
ellular coupling allow us to conclude that growing hyphal 0.6-0.8-mm f
ragment is a functionally independent information-energetic module pos
sessing all the components required for the polarized growth. The expe
rimental model developed can be used for detailed studying the laws of
the interactions between materials and driving forces during polarize
d growth.