Abstract:
:Drosophila melanogaster is a genetically malleable organism with a short life span, making it a tractable system in which to study mechanical effects of genetic perturbation and aging on tissues, e.g., impaired heart function. However, Drosophila heart-tube studies can be hampered by its bilayered structure: a ventral muscle layer covers the contractile cardiomyocytes. Here we propose an atomic force microscopy-based analysis that uses a linearized-Hertz method to measure individual mechanical components of soft composite materials. The technique was verified using bilayered polydimethylsiloxane. We further demonstrated its biological utility via its ability to resolve stiffness changes due to RNA interference to reduce myofibrillar content or due to aging in Drosophila myocardial layers. This protocol provides a platform to assess the mechanics of soft biological composite systems and, to our knowledge, for the first time, permits direct measurement of how genetic perturbations, aging, and disease can impact cardiac function in situ.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Kaushik G,Fuhrmann A,Cammarato A,Engler AJdoi
10.1016/j.bpj.2011.10.042subject
Has Abstractpub_date
2011-12-07 00:00:00pages
2629-37issue
11eissn
0006-3495issn
1542-0086pii
S0006-3495(11)01274-4journal_volume
101pub_type
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