Category Archives: Biochemistry

Beta-cell development and genetics

Two reviews in Trends in Endocrinology and Metabolism (DOI: and DOI: address the development and the pathogenesis of pancreatic β-cells. Conrad, Stein and Hunter describe the transcription factors in mice and man which lead to β-cell genesis while Thomsem and Gloyn focus their attention to malfunction leading diabetes mellitus. Both reviews together show the actual status in β-cell research.

Pre-eclampsia in a line with Alzheimer, Parkinson, and mad cow disease

In an IN DEPTH contribution in Science Nadia Whitehead describes a Science Translational Medicine article (DOI: 10.1126/scitranslmed.3008808) where a team around the doctors Burimshi analyzed urine from 600 pregnant women using the dye Congo red which stains only “bunched”, not properly folded proteins. Those women with a risk of preeclampsia had bunched proteins with a frequency of more than 80 % while healthy women had none. Among the five proteins mostly bunched were immunoglobulin light chains, ceruloplasmin, SERPINA1, albumin and (sic!) Alsheimer’s β-amyloid. The authors conclude that preeclampsia might also be a disease of protein misfolding.

Aside from a new way to look at the disease which affects about 10 % of birth worldwide this paper offers a cheap test for preeclampsia. Remarcable!

Tibetans are different!

A paper in Nature (Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA Emilia Huerta-Sánchez, Xin Jin, Asan et al.) says that DNA in Tibetans to adapt to the altitude can be attributed to an extinguished hominid precursor, the Denisovan: (cited from Nature)

Admixture with other hominin species helped humans to adapt to high-altitude environments; the EPAS1 gene in Tibetan individuals has an unusual haplotype structure that probably resulted from introgression of DNA from Denisovan or Denisovan-related individuals into humans, and this haplotype is only found in Denisovans and Tibetans, and at low frequency among Han Chinese.

A role for BRCA1

The Breast Cancer Risk protein BRCA1 role is becoming analysed. While the mutation/deletion of this protein makes young women (males too) susceptible to develop breast tumours prematurely, how the protein did this was not clear for some time:

While Skully and collegues (doi: 10.1073/pnas.1400783111)  claim a role in replication fork control, Palazzo et al. (doi: 10.4161/cc.27945) observe it is related to the mitotic spindel formation. Chiba and collegue (DOI: 10.1016/j.molcel.2013.10.028) show a complex pattern of BRCA1, its dimerisation partner BARD1 and  the Obg-like ATPase 1, Ola-1 in the organisation of the centrosome.

Therefore, being involved in the basics of the machinery of cellular growth it is clear that BRCA1 once mutated makes the cell instable and prone to neoplastic transformation.