A possible role for the yeast TATA-element-binding protein in DNA replication

Area of Science:

• Molecular Biology
• Genetics
• Yeast Biology

Background:

• The TATA-element-binding protein (TBP) is a crucial transcription initiation factor for all eukaryotic RNA polymerases.
• Its potential role in DNA replication initiation at chromosomal origins has not been fully elucidated.

Purpose of the Study:

• To investigate the involvement of TBP in the initiation of DNA replication at yeast chromosomal origins.
• To determine if TBP binding sites influence replication origin activity.

Main Methods:

• In vitro binding assays using recombinant yeast TBP and DNA fragments from yeast replication origins.
• In vivo functional assays assessing the ability of TBP-binding sites to activate or support DNA replication.
• Site-directed mutagenesis to alter TBP-binding sites and evaluate their impact on replication.

Main Results:

• Recombinant yeast TBP specifically binds to functionally important regions of yeast replication origins in vitro.
• TBP-binding sites from RNA polymerase II promoters can rescue defective replication origins in vivo.
• Mutations reducing TBP affinity in vitro decrease the replication support function of these sites in vivo.

Conclusions:

• TBP is implicated in the initiation of DNA replication at yeast chromosomal origins.
• TBP-binding sites are essential regulatory elements for DNA replication origin function in yeast.