Evolution and functional divergence of the anoctamin family of membrane proteins

Background  

The anoctamin family of transmembrane proteins are found in all eukaryotes and consists of 10 members in vertebrates. Ano1 and ano2 were observed to have Ca²⁺ activated Cl^- channel activity. Recent findings however have revealed that ano6, and ano7 can also produce chloride currents, although with different properties. In contrast, ano9 and ano10 suppress baseline Cl^- conductance when co-expressed with ano1 thus suggesting that different anoctamins can interfere with each other. In order to elucidate intrinsic functional diversity, and underlying evolutionary mechanism among anoctamins, we performed comprehensive bioinformatics analysis of anoctamin gene family.     

Sheep prions with molecular properties intermediate between classical scrapie,BSE and CH1641–scrapie

Efforts to differentiate bovine spongiform encephalopathy (BSE) from scrapie in prion infected sheep have resulted in effective methods to decide about the absence of BSE. In rare instances uncertainties remain due to assumptions that BSE, classical scrapie and CH1641–a rare scrapie variant–could occur as mixtures. In field samples including those from fallen stock, triplex Western blotting analyses of variations in the molecular properties of the proteinase K resistant part of the disease‑associated form of prion protein (PrP^res) represents a powerful tool for quick discrimination purposes. In this study we examined 7 deviant ovine field cases of scrapie for some typical molecular aspects of PrP^res found in CH1641‑scrapie, classical scrapie and BSE. One case was most close to scrapie with respect to molecular mass of its non-glycosylated fraction and N-terminally located 12B2‑epitope content. Two cases were unlike classical scrapie but too weak to differentiate between BSE or CH1641. The other 4 cases appeared intermediate between scrapie and CH1641 with a reduced molecular mass and 12B2‑epitope content, together with the characteristic presence of a second PrP^res population. The existence of these 2 PrP^res populations was further confirmed through deglycosylation by PNGaseF. The findings indicate that discriminatory diagnosis between classical scrapie, CH1641 and BSE can remain inconclusive with current biochemical methods. Whether such intermediate cases represent mixtures of TSE strains should be further investigated e.g. in bioassays with rodent lines that are varying in their susceptibility or other techniques suitable for strain typing.     

Three novel ABCC5 splice variants in human retina and their role as regulators of ABCC5 gene expression

Background  

The ABCC5 gene encodes an organic anion pump of the ATP-binding cassette (ABC) transporter family, subclass C. The exact physiological function of ABCC5 however is not known. Here, we have isolated three novel ABCC5 splice variants and characterized their role in the regulation of ABCC5 gene expression.