Isolation of a yeast tropomyosin-related cDNA clone that encodes a novel transmembrane protein having a C-terminal...

Area of Science:

• Molecular Biology
• Yeast Genetics
• Protein Analysis

Background:

• Tropomyosin is a key protein involved in muscle contraction and cytoskeleton organization.
• Yeast Saccharomyces cerevisiae serves as a model organism for studying eukaryotic gene function.
• Antibody-based screening of cDNA libraries is a common method for gene discovery.

Purpose of the Study:

• To identify and characterize a novel gene from Saccharomyces cerevisiae using an antibody-driven approach.
• To analyze the structural and functional properties of the identified gene product.
• To investigate potential evolutionary or functional links between yeast and human genes.

Main Methods:

• Screening of a Saccharomyces cerevisiae lambda gt11 cDNA library with rabbit anti-rat tropomyosin polyclonal antibody (RTM8-2).
• Analysis of the cDNA clone's open reading frame (ORF) and deduced amino acid sequence.
• Hydropathy plot analysis to predict protein structural features.
• Database searches (EMBL, GenBank) for sequence homology.

Main Results:

• A novel cDNA clone was isolated, containing a 951 bp ORF encoding 317 amino acids.
• The deduced protein sequence exhibits tropomyosin-homologous regions, a transmembrane domain, and a basic C-terminal region.
• The 3' untranslated region (3'UTR) showed 96.9% identity to human cDNA clone 54E05 (EMBL Z15978).

Conclusions:

• The identified yeast gene encodes a protein with structural similarities to tropomyosin.
• The protein possesses predicted transmembrane and basic regions, suggesting potential roles beyond cytoskeletal functions.
• High sequence homology in the 3'UTR indicates a conserved regulatory element or a shared evolutionary origin with human genes.