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Lalani, S. R.

Publications and source records attributed to Lalani, S. R..

2 recordsLinked to original sources

TANGO2 deficient iPSC-differentiated cardiomyocyte and dermal fibroblasts have normal mitochondrial OXPHOS function

Bi-allelic loss-of-function mutations in TANGO2 (Transport and Golgi Organization protein 2) cause a rare multiorgan genetic disorder. Despite normal cardiac function at baseline, patients may experience lethal cardiac arrhythmias during "crises" often associated with metabolic stresses such as fasting, viral illness and fever. The molecular function of TANGO2 remains largely unknown. Previous studies have suggested a functional association with the mitochondrion, however definitive evidence is lacking. Further, functional impact of TANGO2 deficiency on mitochondrial function has not been investigated in a cardiac model. In this study, we utilized a recently developed patient-derived induced pluripotent stem cell differentiated cardiomyocytes (iPSC-CM) model by our group, along with patient-derived dermal fibroblast model, to interrogate whether loss of TANGO2 function leads to defective mitochondrial function. Both baseline and fasting condition were investigated. Oxygen consumption rate (OCR) was measured in Seahorse assays to assess mitochondrial function in vitro. The results showed both TANGO2 deficient dermal fibroblasts and iPSC-CM had no apparent defects in mitochondrial oxidative phosphorylation (OXPHOS) function under either baseline or fasting condition. Based on our study, we conclude that the lethal cardiac arrhythmias in TANGO2 patients are unlikely to be related to impaired mitochondrial OXPHOS function in the cardiomyocytes.

cell biology↗

Microdeletions excluding YWHAE and PAFAH1B1 cause a unique leukoencephalopathy and hypermobility syndrome: Further delineation of the 17p13.3 microdeletion spectrum

PurposeBrain malformations are caused by 17p13.3 deletions: lissencephaly with deletions of the larger Miller-Dieker syndrome region or smaller deletions of only PAFAH1B1, as well as various abnormalities, including white matter changes, in the distinct syndrome due to deletions including YWHAE and CRK but sparing PAFAH1B1. We sought to understand the significance of 17p13.3 deletions between the YWHAE/CRK and PAFAH1B1 loci.\n\nMethodsWe analyzed the clinical features of five individuals from four families with 17p13.3 deletions between and not including YWHAE/CRK and PAFAH1B1 identified among individuals undergoing clinical chromosomal microarray testing.\n\nResultsFour individuals from three families have multi-focal white matter lesions and hypermobile joints, while a fifth had a normal MRI. A combination of our patients and a review of those in the literature with white matter changes and deletions in this chromosomal region narrows the overlapping region for this brain phenotype to [~]345 kb, including 11 RefSeq genes, with RTN4RL1 haploinsufficiency as the best candidate for causing this.\n\nConclusionWhile previous literature has hypothesized dysmorphic features and white matter changes related to YWHAE, our cohort contributes evidence to the presence of additional genes within 17p13.3 required for proper brain development.

genetics↗