• Fulltext


        Click here to view fulltext PDF

      Permanent link:

    • Keywords


      Cancer cells; 𝛽-galactoside 𝛼2,6-sialyltransferase I; promoter; siat 1 gene

    • Abstract


      The level of 𝛽-galactoside 𝛼2,6-sialyltransferase I (ST6Gal I) mRNA, encoded by the gene siat1, is increased in malignant tissues. Expression is regulated by different promoters – P1, P2 and P3 – generating three mRNA isoforms H, X and YZ. In cervical cancer tissue the mRNA isoform H, which results from P1 promoter activity, is increased. To study the regulation of P1 promoter, different constructs from P1 promoter were evaluated by luciferase assays in cervical and hepatic cell lines. Deletion of a fragment of 1048 bp (−89 to +24 bp) increased 5- and 3-fold the promoter activity in C33A and HepG2 cell lines, respectively. The minimal region with promoter activity was a 37 bp fragment in C33A cells. The activity of this region does not require the presence of an initiator sequence. In HepG2 cells the minimal promoter activity was detected in the 66 bp fragment. Sp1 (−32) mutation increased the promoter activity only in HepG2 cells. HNF1 mutation decreased promoter activity in HepG2 cell line but not in C33A cells. We identified a large region that plays a negative regulation role. The regulation of promoter activity is cell type specific. Our study provides new insights into the complex transcriptional regulation of siat1 gene.

    • Author Affiliations


      Lorena Milflores-Flores1 2 Lourdes Millán-Pérez3 Gerardo Santos-López1 Julio Reyes-Leyva1 Verónica Vallejo-Ruiz1

      1. Laboratorio de Biología Molecular y Virología, Centro de Investigación Biomédica de Oriente, Instituto Mexicano del Seguro Social, Hospital General de Zona No. 5, Km 4.5 Carretera Federal Atlixco-Metepec, 74360 Metepec, Puebla, México
      2. Área de Bioquímica y Biología Molecular, Posgrado en Ciencias Químicas, BUAP, Blvd. 14 Sur Esq. San Claudio, CU. Col. San Manuel, Puebla, México
      3. Centro de Química, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, México
    • Dates

  • Journal of Biosciences | News

      Forthcoming Special issue.

    • To trigger further research on plant mitochondria, the Journal of Biosciences is bringing out a special issue titled "Plant Mitochondria: Properties and Interactions with Other Organelles".

      Plant mitochondria are quite distinct and have unique features, such as a cyanide-insensitive alternate pathway. They also interact with chloroplasts to optimize photosynthetic carbon assimilation.

      Submissions are welcome until 30 July 2023. The contributions can be original articles, short communications, reviews, or mini-reviews on any topic related to plant mitochondria.

      Authors can submit their articles online at https://www.editorialmanager.com/jbsc/default2.aspx

      Posted on April 12, 2023
    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2022-2023 Indian Academy of Sciences, Bengaluru.