Mutations in MAP3K1 that cause 46,XY disorders of sex development disrupt distinct structural domains in the protein

Missense mutations in the gene, MAP3K1, are a common cause of 46,XY gonadal dysgenesis, accounting for 15-20% of cases [Ostrer, 2014, Disorders of sex development (DSDs): an update. J. Clin. Endocrinol. Metab., 99, 1503-1509]. Functional studies demonstrated that all of these mutations cause a protein gain-of-function that alters co-factor binding and increases phosphorylation of the downstream MAP kinase pathway targets, MAPK11, MAP3K and MAPK1. This dysregulation of the MAP kinase pathway results in increased CTNNB1, increased expression of WNT4 and FOXL2 and decreased expression of SRY and SOX9. Unique and recurrent pathogenic mutations cluster in three semi-contiguous domains outside the kinase region of the protein, a newly identified N-terminal domain that shares homology with the Guanine Exchange Factor (residues Met164 to Glu231), a Plant HomeoDomain (residues Met442 to Trp495) and an ARMadillo repeat domain (residues Met566 to Glu862). Despite the presence of the mutation clusters and clinical data, there exists a dearth of mechanistic insights behind the development imbalance. In this paper, we use structural modeling and functional data of these mutations to understand alterations of the MAP3K1 protein and the effects on protein folding, binding and downstream target phosphorylation. We show that these mutations have differential effects on protein binding depending on the domains in which they occur. These mutations increase the binding of the RHOA, MAP3K4 and FRAT1 proteins and generally decrease the binding of RAC1. Thus, pathologies in MAP3K1 disrupt the balance between the pro-kinase activities of the RHOA and MAP3K4 binding partners and the inhibitory activity of RAC1.

Rapid Next-Generation Sequencing Method for Prediction of Prostate Cancer Risks

Prostate cancer is the most commonly diagnosed male cancer and the second leading cause of cancer deaths among men in the United States, with approximately 220,000 new diagnoses and approximately 27,000 deaths each year. Men with clinical low-risk disease can receive active surveillance to safely preserve quality of life, provided that the risk of an undetected aggressive cancer can be managed. Thus, prediction of a tumor's metastatic potential, ideally using only a biopsy sample, is critical to choosing appropriate treatment. We previously proposed and verified a metastasis potential score (MPS) based on regions prone to copy number alterations in metastatic prostate cancer; MPS is highly predictive of metastatic potential in primary tumors. We developed a novel, targeted postligation amplification sequencing approach, which we call the next-generation copy number alteration assay, to efficiently interrogate 902 genomic sites that belong to 194 genomic regions used in the MPS calculation. The assay is designed to work with the latest generation of sequencing platforms to produce estimates of copy number alteration events. The assay's technical reproducibility, robustness to low starting genomic material, and accuracy have been verified. The assay performed very well on cell lines, a cohort of prostate cancer surgical research samples, and matched punched biopsy samples, making it a significant step toward incorporating sequencing techniques for prostate cancer evaluation.