PanK2

PanK2 (pantothenate kinase 2) is a mitochondrial pantothenate kinase that catalyzes the ATP-dependent phosphorylation of pantothenate, the first and rate-limiting step of coenzyme A (CoA) biosynthesis, thereby controlling a central metabolic pathway required for cellular energy and lipid metabolism^[1][2]. Mechanistically, PanK2 functions within the CoA biosynthetic network and contributes to mitochondrial regulation of CoA homeostasis, linking vitamin B5 utilization to downstream metabolic processes^[2][3]. Because CoA is an essential cofactor for numerous mitochondrial reactions, disruption of PANK2 directly affects cellular metabolic integrity and mitochondrial function^[3][1]. Disease relevance is highlighted by the discovery that loss-of-function mutations in PANK2 cause pantothenate kinase-associated neurodegeneration (PKAN), the most common form of neurodegeneration with brain iron accumulation (NBIA), characterized by progressive neurological dysfunction and brain iron deposition^[1][4]. Experimental studies and disease models have therefore used PANK2 deficiency to investigate the relationship between impaired CoA metabolism, mitochondrial dysfunction, and neurodegeneration^[3][4]. Compared with related pantothenate kinase isoforms, PanK2 is distinguished by its mitochondrial localization and is considered the only mitochondrial member of the human PANK family, indicating a specialized role in compartmentalized CoA regulation^[2][5]. For experimental applications, PanK2 activity is regulated by CoA and acyl-CoA species, whereas palmitoylcarnitine has been reported to activate the enzyme, providing a biochemical framework for mechanistic studies of CoA metabolism and PKAN pathogenesis^[3].