BFSP2 is a gene that encodes the proteinphakinin ("beaded filament structural protein 2") in humans.[5]
More than 99% of the vertebrate ocular lens consists of terminally differentiated lens fiber cells. Two lens-specific intermediate filament proteins, the protein product of this gene (CP49 or phakinin) and filensin (also known as CP115), are expressed only after fiber cell differentiation has begun. Both proteins are found in a structurally unique cytoskeletal element that is referred to as the beaded filament (BF). Mutations in this gene have been associated with juvenile-onset, progressive cataracts and Dowling-Meara epidermolysis bullosa simplex.[5]
The two BFSP proteins are put into a "type VI" of intermediate filament (IF) classification. Unlike other IFs that form unbranched links, the two proteins form a network of filaments together with CRYAA.[6][7]
Carter JM, McLean WH, West S, Quinlan RA (April 2000). "Mapping of the human CP49 gene and identification of an intragenic polymorphic marker to allow genetic linkage analysis in autosomal dominant congenital cataract". Biochemical and Biophysical Research Communications. 270 (2): 432–436. doi:10.1006/bbrc.2000.2442. PMID10753642.
Zhang Q, Guo X, Xiao X, Yi J, Jia X, Hejtmancik JF (November 2004). "Clinical description and genome wide linkage study of Y-sutural cataract and myopia in a Chinese family". Molecular Vision. 10: 890–900. PMID15570218.
Zhang L, Gao L, Li Z, Qin W, Gao W, Cui X, et al. (December 2006). "Progressive sutural cataract associated with a BFSP2 mutation in a Chinese family". Molecular Vision. 12: 1626–1631. PMID17200662.
Cui X, Gao L, Jin Y, Zhang Y, Bai J, Feng G, et al. (October 2007). "The E233del mutation in BFSP2 causes a progressive autosomal dominant congenital cataract in a Chinese family". Molecular Vision. 13: 2023–2029. PMID17982427.
