How Localized Z-Disc Damage Affects Force Generation and Gene Expression in Cardiomyocytes

Area of Science:

• Cardiovascular Biology
• Cellular Mechanics
• Stem Cell Research

Background:

• The Z-disc is crucial for cardiomyocyte (CM) function and sarcomeric cytoskeletal organization.
• Understanding Z-disc related cardiomyopathies requires novel models of Z-disc damage.
• Human pluripotent stem cell (hPSC)-derived CMs offer an in vitro model for studying the sarcomeric cytoskeleton.

Purpose of the Study:

• To develop and utilize a novel model for Z-disc damage in hPSC-derived CMs.
• To investigate the functional and transcriptional consequences of Z-disc manipulation.
• To gain insights into Z-disc related cardiomyopathies and potential therapeutic strategies.

Main Methods:

• Utilized a femtosecond laser system for precise Z-disc ablation in hPSC-derived CMs.
• Assessed changes in force generation using traction force microscopy.
• Analyzed gene expression profiles to identify transcriptional responses to Z-disc damage.

Main Results:

• Significant reduction in force generation observed after Z-disc removal.
• No significant alteration in contraction frequency detected post-manipulation.
• Upregulation of stress-related gene NF-kB, ACTN2, and FLNc observed.
• Downregulation of cardiac troponin I (TNNI3) and cardiac muscle troponin T (TNNT2) noted.

Conclusions:

• Z-disc damage in hPSC-derived CMs leads to impaired force generation and specific gene expression changes.
• Findings elucidate the transcriptional coupling between Z-disc damage and functional deficits.
• This research provides a foundation for developing novel therapies for sarcomeric disorders.