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Asymmetrical distribution of Neisseria miniature insertion sequence DNA repeats among pathogenic and nonpathogenic

Eliana De Gregorio1, Chiara Abrescia, M Stella Carlomagno

  • 1Dipartimento di Biologia e Patologia Cellulare e Molecolare, L. Califano, Università degli Studi di Napoli Federico II, 80131 Naples, Italy.

Infection and Immunity
|June 24, 2003
PubMed

Insights

Neisseria miniature insertion sequences (nemis) are DNA elements found in Neisseria species. Most nemis were conserved in Neisseria meningitidis but not N. lactamica, suggesting posttranscriptional gene regulation in meningococci.

Area of Science:

  • Microbiology
  • Genetics
  • Molecular Biology

Background:

  • Neisseria miniature insertion sequences (nemis) are repetitive DNA elements identified in Neisseria bacteria.
  • These elements possess unique structural features, including terminal hairpins crucial for their function.

Purpose of the Study:

  • To investigate the conservation and distribution of nemis in different Neisseria species.
  • To explore the potential role of nemis in posttranscriptional gene regulation.

Main Methods:

  • Polymerase chain reaction (PCR) was employed to analyze 57 nem elements flanking cellular genes.
  • Comparative analysis was performed between Neisseria meningitidis and Neisseria lactamica strains.

Main Results:

  • A significant conservation of nem elements was observed in Neisseria meningitidis.
  • Conversely, these nem elements were largely absent in Neisseria lactamica strains.
  • The study identified that mRNAs spanning nemis are processed by RNase III at hairpin structures.

Conclusions:

  • Nemis exhibit differential conservation across Neisseria species, with higher prevalence in N. meningitidis.
  • The RNase III processing of nemi-spanning mRNAs suggests a mechanism for selective posttranscriptional gene regulation in N. meningitidis.

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