1

Mother celi.

Developing

SPORE

FIGURĘ 9.07 Outline of Spore Formation Regulatory Cascade

A cascade of four sigma factors is involved in the stepwise development of the spore in Bacillus. An external signal activates synthesis of oF in the spore. This is required for transcription of the gene for aG (inside spore) and for factors that cross into the mother celi (red arrow) and convert pre-oE into active aE (in mother celi).

Active oE is required for synthesis of the precursor, pre-aK. Finally, aG allows synthesis of factors that cross into the mother celi (red arrow) and convert pre-oK into active oK (in mother celi).

a F

Needed

FOR

TRANSCRIPTION

LU

cc

0

u.

(/)

Q

1

D

0

u:

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j

Actiration

signals

Nf.eded

for

TRANSCRIPTION

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Activaiion

signals