Disease relevance of hetC

• Unlike those of the wild-type strain, proheterocysts of the Anabaena sp. strain PCC 7120 hetC strain keep dividing. ftsZ, the most critical cell division gene, is up-regulated in hetC proheterocysts [1].
• Heterocyst differentiation in the cyanobacterium Anabaena sp. strain PCC 7120 requires NtcA, the global nitrogen regulator in cyanobacteria, and HetR, the master regulator of heterocyst differentiation [2].

High impact information on hetC

• Calcium ions are important to some prokaryotic cellular processes, such as heterocyst differentiation of cyanobacteria [3].
• We demonstrate here that CcbP is degraded by HetR, a serine-type protease that controls heterocyst differentiation [3].
• Expression of the hetC gene, which is also involved in the early steps of heterocyst differentiation, from its NtcA-dependent tsp was, however, not dependent on HetR [4].
• MinC overexpression blocked heterocyst differentiation, consistent with the requirement of cell division in the control of heterocyst development [5].
• Expression of hetC, tested by RNA- DNA hybridization, was impaired in an ntcA mutant [6].

Biological context of hetC

• Sequence analysis of chromosomal DNA adjacent to the ends of transposon Tn5-1058 in mutant C3 showed a 1,044-amino-acid open reading frame, designated hetC, whose predicted protein product throughout its C-terminal two-thirds has extensive similarity to the HlyB family of bacterial protein exporters [7].

Other interactions of hetC

• The transcription regulator NtcA is required for the initiation of heterocyst formation. hetL overexpression allowed the initiation of heterocyst development in an ntcA-null mutant, but differentiation was incomplete. hetR and hetC mutations that block heterocyst development are epistatic to hetL overexpression [8].
• Its N-terminal third is unique and does not resemble any known protein. hetC lies 1,165 bp 5' from the previously described gene hetP [7].
• Highly similar sequences are present 5' from the initiation codons and in the 3' untranslated regions of hetC and of two heterocyst-specific genes, devA and hetP [7].

References