A multiprotein complex that interacts with RNA polymerase II elongator.

Area of Science:

• Molecular Biology
• Yeast Genetics
• Protein Interactions

Background:

• The Elongator complex is crucial for transcription and other cellular processes.
• The Hap complex is known to regulate gene expression in yeast.
• Interactions between transcription factors and RNA polymerase II machinery are vital for gene regulation.

Purpose of the Study:

• To investigate the interaction between the Hap complex and RNA polymerase II Elongator in yeast.
• To elucidate the functional significance of this interaction.
• To identify the specific Hap subunits involved in the interaction and their roles.

Main Methods:

• Isolation of a three-subunit Hap complex from yeast.
• Genetic analysis using gene deletions for Hap subunits (HAP1, HAP3).
• Phenotypic analysis of deletion mutants, including pGKL killer sensitivity and Elongator function assays.
• Biochemical assays to study the interaction between the Hap complex and Elongator.

Main Results:

• A three-subunit Hap complex that interacts with RNA polymerase II Elongator was successfully isolated.
• Deletion of HAP1 or HAP3 genes resulted in pGKL killer-insensitive phenotypes.
• These deletions also led to a weak Elongator phenotype, indicating functional involvement.
• The Hap complex preferentially interacts with free Elongator over RNA polymerase II-associated Elongator.

Conclusions:

• The Hap complex plays a regulatory role in Elongator activity.
• Specific Hap subunits (HAP1 and HAP3) are essential for proper Elongator function and cellular responses.
• The interaction dynamics suggest a mechanism for modulating Elongator function in response to cellular signals.