Epistatic Relationships of Two Regulatory Factors During Heterocyst Development

다국어 초록 (Multilingual Abstract)

The filamentous cyanobacterium Anabaena sp. Strain PCC 7120 produces a developmental pattern of single heterocysts
separated by approximately 10 vegetative cells. Heterocysts differentiate from vegetative cells and are specialized
for nitrogen fixation. The patS gene, which encodes a small peptide that inhibits heterocyst differentiation, is
expressed in proheterocysts and plays a critical role in establishing the heterocyst pattern. Another key regulator of
heterocyst development is the hetR gene. hetR mutants fail to produce heterocysts and extra copies of hetR on a plasmid
cause a multiple contiguous heterocyst phenotype. To elucidate the relationship between these two counter acting
factors in the genetic regulatory pathway during heterocyst differentiation, the expression patterns of a patS-gfp
and a hetR-gfp fusion were examined in a patS deletion and a hetR deletion strain. The results, in combination with
the result from a hetR and patS double deletion strain, suggest patS and hetR are mutually antagonistic and the balance
between these two factors in two different cell types (heterocysts and vegetative cells) may be critical during
the decision making process on their cell fates.

참고문헌 (Reference)

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