DDX39B and amyotrophic lateral sclerosis: Quantitation of these blots showed a trend towards increased binding of both Aly and Ddx39b to the S85C and P154S mutations in Matrin 3, while increased binding of S85C Matrin 3 to Ddx39b reached statistical significance (Fig. 4e,f).Co-immunopreciptiation between Matrin 3 and Ddx39b was also performed in human post-mortem lumbar spinal cord tissue, confirming that these proteins interact in vivo and in the context of sporadic ALS (Fig. 4g).