Carboxyl ester lipase hybrid 1 (CEL-HYB1) haplotypes confer varying risk for chronic pancreatitis.

The CEL-HYB1 hybrid allele of the carboxyl ester lipase (CEL) gene and its pseudogene (CELP) has been associated with chronic pancreatitis (CP). Recent work indicated that amino acid positions 488 and 548 in CEL-HYB1 determined pathogenicity. Haplotype Thr488-Ile548 was associated with CP while haplotypes Thr488-Thr548 and Ile488-Thr548 were benign.

Heterogeneous force response of chromatin in isolated nuclei.

A quantitative description of nuclear mechanics is crucial for understanding its role in force sensing within eukaryotic cells. Recent studies indicate that the chromatin within the nucleus cannot be treated as a homogeneous material. To elucidate its material properties, we combine optical tweezers manipulation of isolated nuclei with multi-color fluorescence imaging of lamin and chromatin to map the response of nuclei to local deformations.

Ion-mediated condensation controls the mechanics of mitotic chromosomes.

During mitosis in eukaryotic cells, mechanical forces generated by the mitotic spindle pull the sister chromatids into the nascent daughter cells. How do mitotic chromosomes achieve the necessary mechanical stiffness and stability to maintain their integrity under these forces? Here we use optical tweezers to show that ions involved in physiological chromosome condensation are crucial for chromosomal stability, stiffness and viscous dissipation. We combine these experiments with high-salt histone depletion and theory to show that chromosomal elasticity originates from the chromatin fibre behaving as a flexible polymer, whereas energy dissipation can be explained by modelling chromatin loops as an entangled polymer solution.