{'fraction_non_alphanumeric': 0.02609727164887307, 'fraction_numerical': 0.0166073546856465, 'mean_word_length': 4.9020979020979025, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 1, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Localized Induction of the ntcA Regulatory Gene in Developing Heterocysts of Anabaena sp. Strain PCC 7120

ABSTRACT The ntcA gene encodes an N-control transcriptional regulator in cyanobacteria. In the N2-fixing, heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120, ntcA is an autoregulatory gene that is transcribed from a complex promoter region that includes a constitutive promoter (P2) and promoters that are induced upon N step-down (P1 and P3). Expression of ntcA was investigated with the use of an ntcA-gfp translational fusion, which was introduced both in the natural ntcA locus and in a heterologous genomic place. Induction of ntcA-gfp took place after N step-down in all the cells of the filament, but at especially high levels in developing heterocysts. Localized induction could be driven independently by P3 and P1.