Telomerase Interaction Partners-Insight from Plants.

Area of Science:

• Plant molecular biology
• Cellular biology
• Biochemistry

Background:

• Telomerase is crucial for maintaining chromosome ends (telomeres) and genome stability.
• Existing models for telomerase assembly and function are incomplete, especially regarding non-telomeric roles.
• Understanding telomerase interactions is key to elucidating its multifaceted functions.

Purpose of the Study:

• To investigate protein interactions with the Arabidopsis telomerase protein subunit (AtTERT) and POT1a.
• To identify novel components of the telomerase holoenzyme and its associated network.
• To explore telomerase's role in chromatin assembly, replication, and other cellular processes.

Main Methods:

• Protein-protein interaction studies using Arabidopsis thaliana.
• Targeted investigation of 176 candidate proteins interacting with AtTERT and/or POT1a.
• Analysis of protein domains responsible for binding and subcellular localization of interactions.

Main Results:

• Identified interactions between telomerase components (AtTERT, POT1a) and nucleosome assembly proteins (NAP) and the minichromosome maintenance (MCM) system.
• Revealed numerous interactions with nucleolar, transport, ribosomal proteins, and molecular chaperones during telomerase biogenesis.
• Discovered additional interaction networks for NAP proteins and DOMINO1, linking telomerase to chromatin remodeling and cell differentiation.

Conclusions:

• Telomerase interacts with complexes involved in chromatin assembly and DNA replication, suggesting roles beyond telomere maintenance.
• The study provides a broader view of telomerase's intracellular life, including its biogenesis and connections to diverse cellular pathways.
• These findings advance our understanding of telomerase's functional network in plants, with implications for genome integrity and development.