UNC-45B is a crucial chaperone protein that aids in myosin folding and assembly and is an essential component for sarcomeric organization in muscle cell development and myofibrillogenesis. UNC45B is exclusively expressed in striated muscles and comprises 3 conserved domains: the N-terminal triple tetratricopeptide repeat (TPR) domain, the central domain of armadillo repeats and the C-terminal UNC45/Cro1/She4p (UCS) domain. The C-terminal UCS domain predominantly mediates the chaperone activity of UNC45B and is crucial for myosin binding, and induces a protective response under stressful conditions, stabilizing myosin and preventing aggregation. The central domain binds the myosin motor domain independent of UCS-myosin binding and exhibits inhibitory effects on the myosin motor domain, halting the power stroke and preventing myosin-mediated actin translocations. The TPR domain interacts with another chaperone protein, the heat shock protein 90 (Hsp90), with which UNC-45B forms a stable complex, binding unfolded myosin motor domains and promoting its folding, as well as mediating a protective response to disruptions in myosin homeostasis. A novel missense mutation in an evolutionarily conserved residue of one of the domains of UNC-45B has recently been identified to be associated with hypertrophic cardiomyopathy by whole exome sequencing. To assess the structural effects of this mutation, rat cardiomyocytes were transfected with GFP-labeled wild-type and mutant UNC-45, and immunostaining was performed to produce an illustration of the morphological effects of the mutation in question. Western blot was also performed to validate the presence of UNC-45 proteins in transfected samples. The results generated in this study were deemed inconclusive and no significant conclusions can be made regarding the possible effects of this mutant variant on sarcomeric organization.