Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES) to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF) and aquaporin-1 (AQP-1) was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI) scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p<0.01) at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE) staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

Geoglossomycetes cl. nov., Geoglossales ord. nov. and taxa above class rank in the Ascomycota Tree of Life

Featuring a high level of taxon sampling across Ascomycota, we evaluate a multi-gene phylogeny and propose a novel order and class in Ascomycota. We describe two new taxa, Geoglossomycetes and Geoglossales, to host three earth tongue genera: Geoglossum, Trichoglossum and Sarcoleotia as a lineage of 'Leotiomyceta'. Correspondingly, we confirm that these genera are not closely related to the genera Neolecta, Mitrula, Cudonia, Microglossum, Thuemenidum, Spathularia and Bryoglossum, all of which have been previously placed within the Geoglossaceae. We also propose a non-hierarchical system for naming well-resolved nodes, such as 'Saccharomyceta', 'Dothideomyceta', and 'Sordariomyceta' for supraordinal nodes, within the current phylogeny, acting as rankless taxa. As part of this revision, the continued use of 'Leotiomyceta', now as a rankless taxon, is proposed.

Cloning and characterization of a pyridoxine 5'-phosphate oxidase from silkworm, Bombyx mori

A cDNA encoding Pyridoxine 5'-phosphate oxidase (PNPO) from Bombyx mori was cloned and characterized (GenBank accession number: DQ452398). The cDNA encodes a polypeptide of 257 amino acid residues. The recombinant enzyme purified from Escherichia coli exhibited maximal activity at pH 9.0, and the K(m) values for the substrates of pyridoxine 5'-phosphate and pyridoxamine 5'-phosphate were determined as 0.65 and 1.15 micromol/l. It was found that B. mori PNPO shares 51.44% homology with humans, but several function-related, key amino acid residues in B. mori PNPO are different from the human and E. Coli gene. B. mori has a single copy of the PNPO gene, which spans a 3.5 kb region and contains five exons and four introns. B. mori PNPO is a homodimer, with each monomer containing nine antiparallel beta-strands and five alpha-helical segments. The secondary structure was deduced from computational study.