Antisense oligonucleotides correct the familial dysautonomia splicing defect in IKBKAP transgenic mice
NUCLEIC ACIDS RESEARCH
Authors: Sinha, Rahul; Kim, Young Jin; Nomakuchi, Tomoki; Sahashi, Kentaro; Hua, Yimin; Rigo, Frank; Bennett, C. Frank; Krainer, Adrian R.
Abstract
Familial dysautonomia (FD) is a rare inherited neurodegenerative disorder caused by a point mutation in the IKBKAP gene that results in defective splicing of its pre-mRNA. The mutation weakens the 5' splice site of exon 20, causing this exon to be skipped, thereby introducing a premature termination codon. Though detailed FD pathogenesis mechanisms are not yet clear, correcting the splicing defect in the relevant tissue(s), thus restoring normal expression levels of the full-length IKAP protein, could be therapeutic. Splice-switching antisense oligonucleotides (ASOs) can be effective targeted therapeutics for neurodegenerative diseases, such as nusinersen (Spinraza), an approved drug for spinal muscular atrophy. Using a two-step screen with ASOs targeting IKBKAP exon 20 or the adjoining intronic regions, we identified a lead ASO that fully restored exon 20 splicing in FD patient fibroblasts. We also characterized the corresponding cis-acting regulatory sequences that control exon 20 splicing. When administered into a transgenic FD mouse model, the lead ASO promoted expression of full-length human IK-BKAP mRNA and IKAP protein levels in several tissues tested, including the central nervous system. These findings provide insights into the mechanisms of IKBKAP exon 20 recognition, and pre-clinical proof of concept for an ASO-based targeted therapy for FD.
New exact solutions for coupled nonlinear system of ion sound and Langmuir waves
INDIAN JOURNAL OF PHYSICS
Authors: Shakeel, M.; Iqbaol, M. A.; Din, Q.; Hassan, Q. M.; Ayub, K.
Abstract
In this work, our main goal is to study a new wave behavior of the nonlinear system associated with ionic wave equations under the influence of the ponderomotive force caused by a nonlinear force experienced by a charged particle in an inhomogeneous oscillating electromagnetic field due to high-frequency field. Another variation in the modified exp-function method has been developed to find progressive wave solutions for the system of sound waveform equations under the pressure of Langmuir wave. The algorithm presented in this work offers new solutions for the complex redundant functions of the nonlinear system in relation to the considered model. Numerical simulations are provided to illustrate the effectiveness of proposed algorithm.