Effect of new founders on retention of gene diversity in captive populations: A formalization of the nucleus population concept

A nucleus population is a small captive population genetically supported by periodic importation of wild caught animals. Periodic importation will allow nucleus populations to maintain the same amount of gene diversity as larger captive populations that do not import wild caught animals. The function of nucleus populations as envisioned by the IUCN/SSC Captive Breeding Specialist Group (CBSG) is to make additional captive space available for endangered taxa not currently maintained in captivity. In this article, mathematical models are developed to assess the effectiveness of the nucleus population concept in reducing the population sizes necessary to maintain appreciable amounts of gene diversity in captive populations. It is shown that the Nucleus I population concept, as defined and promoted by the CBSG, requires an importation rate 10–20 times greater than they have indicated. Whereas nucleus populations are not appropriate for maintenance of significant amounts of gene diversity in long-term breeding programs, small populations can be valuable for research, education, and reintroduction projects with short-term goals. Decisions have to be made on which of the many endangered taxa will be maintained and for what purposes, if captive breeding is to be an effective component of species conservation. © 1993 Wiley-Liss, Inc.     

Identification,occurrence, incidence and transmission of phytoplasma associated with Petunia violacea witches’ broom in Iran

A petunia witches’ broom (PvWB) disease, characterized by phyllody, virescence, witches’ broom, little leaf and yellowing, was observed in municipal lands and parks in Bandar Abbas, Hormozgan province, Iran. The disease was present with an average incidence of 20%. PCR and sequencing analysis carried out on selected samples from symptomatic plants showed the presence of a phytoplasma associated with the disease. The molecular comparison of the 16S ribosomal gene indicated 99% sequence identity with the one of “Candidatus Phytoplasma australasia”. This phytoplasma was transmitted to healthy petunia plants under experimental conditions by the leafhopper Orosius albicinctus that was then demonstrated to be a vector of this phytoplasma.     

DNA Methylation and Histone H1 Jointly Repress Transposable Elements and Aberrant Intragenic Transcripts

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Energetics and protomer communication in the dynamical structure of S100A13 in free and protein-bound states

S100A13 is S100 family of EF-hand-containing calcium-binding protein involved in the secretion of some growth factors and pro-inflammatory cytokines lacking signal peptides. The involvement of S100A13 in cancer progression and inflammatory diseases has been reported. In this study, structures generated during atomistic molecular dynamics simulation were studied. Dynamical network analysis data revealed that native inter-protomer communication network driven principally by vdW interaction (~550 kj/mol) is altered (Receptor for advanced glycation end products (RAGE) C2- and Fibroblast growth factor (FGF)-1-bound S100A13) or completely abolished (interleukin-1 (IL1)-α- and C2A-p40Syt1-bound S100A13) in protein-bound S100A13 homodimer. Bulk water density (weighted atomic density) around exposed S100A13 homodimer surface explored tends to follow the dynamical network lead as S100A13 homodimer appeared densely solvated in C2A-p40Syt1- and IL1)-α-bound states but not in RAGE C2- and FGF-1-bound biosystems. Furthermore, projection of radius of gyration and root mean square deviation (from native structure) variables of the generated structures along the 3D-free energy surface showed anti-parallel β-sheet proximal to Ca²⁺-binding loops-I/II in most metastable complexes retrieved from energy minima state with strong indications for β-sheet network formation during protein binding. Interaction between S100A13 homodimer and ligand–proteins may be dictated by the strength of vdW and electrostatic interaction with possible involvement of bulk water desolvation in some complexes. All these results strongly suggest that disruption of multiprotein receptor complex can be achieved by designing specific compounds targeting a specific aspect of S100A13/protein interaction; such drugs may have clinical usefulness in blocking angiogenesis, reversing cell proliferation and attenuating inflammatory processes.     

A protein in rat prostatic interacting with androgen regulated gene

2M NaCl-insoluble fraction of rat ventral prostatechromatin(residual proteins)contain proteins able tointeract specifically with androgen-receptor complex andis,therefore,a part of the acceptor complex.Amongresidual proteins,a 97 KDa protein has been found whichbinds signifieantly to a genomic fragment containingan androgen-regulated gene coding for a 22 KDa protein.The biological significance of this binding in androgenaction need to be further studied. A mini-plasmid clone containing 22 KDa proteincoding sequence was cloned into Charon 4A genomiclibrary from which a 5.7 Kb genomic fragment wasisolated,identified by hybridization with a 5' and a 3'cDNA probes,and shown to contain the 5' flankingsequence.Restriction enzyme treatment of this fragmentyielded a 4.7 Kb restriction fragment representingthe 5' upstream region and a 1.0 Kb containing part ofthe coding sequence.Deletion studies indicated that the97 KDa protein bound only to a subclone of about 300 bpsegment.Furthermore,gel shifting experiment supportedits DNA-prptein binding.     

An Optimized Proteomics Approach Reveals Novel Alternative Proteins in Mouse Liver Development

Alternative ORFs (AltORFs) are unannotated sequences in genome that encode novel peptides or proteins named alternative proteins (AltProts). Although ribosome profiling and bioinformatics predict a large number of AltProts, mass spectrometry as the only direct way of identification is hampered by the short lengths and relative low abundance of AltProts. There is an urgent need for improvement of mass spectrometry methodologies for AltProt identification. Here, we report an approach based on size-exclusion chromatography for simultaneous enrichment and fractionation of AltProts from complex proteome. This method greatly simplifies the variance of AltProts discovery by enriching small proteins smaller than 40 kDa. In a systematic comparison between 10 methods, the approach we reported enabled the discovery of more AltProts with overall higher intensities, with less cost of time and effort compared to other workflows. We applied this approach to identify 89 novel AltProts from mouse liver, 39 of which were differentially expressed between embryonic and adult mice. During embryonic development, the upregulated AltProts were mainly involved in biological pathways on RNA splicing and processing, whereas the AltProts involved in metabolisms were more active in adult livers. Our study not only provides an effective approach for identifying AltProts but also novel AltProts that are potentially important in developmental biology.     

Doxorubicin-induced alterations in kidney functioning,oxidative stress,DNA damage,and renal tissue morphology; Improvement by Acacia hydaspica tannin-rich ethyl acetate fraction

Doxorubicin (DOX) is an anthracycline drug used for cancer treatment. However, its treatment is contiguous with toxic effects. We examined the nephroprotective potential of A. hydaspica polyphenol-rich ethyl acetate extract (AHE) against DOX persuaded nephrotoxicity. 36 male Sprague Dawley rats were randomly assorted into 6 groups. Control group received saline; DOX group: 3 mg/kg b.w. dosage of DOX intraperitoneally for 6 weeks (single dose/week). In co-treatment groups, 200 and 400 mg/kg b.w AHE was given orally for 6 weeks in concomitant with DOX (3 mg/kg b.w, i.p. injection per week) respectively. Standard group received silymarin 400 mg/kg b.w daily + DOX (single dose/week). Biochemical kidney function tests, oxidative stress markers, genotoxicity, antioxidant enzyme status, and histopathological changes were examined. DOX caused significant body weight loss and decrease kidney weight. DOX-induced marked deterioration in renal function indicators in both urine and serum, i.e., PH, specific gravity, total protein, albumin, urea, creatinine, uric acid, globulin, blood urea nitrogen, etc. Also, DOX treatment increases renal tissue oxidative stress markers, while lower antioxidant enzymes in tissue along with degenerative alterations in the renal tissue compared to control rats. AHE co-treatment ameliorates DOX-prompted changes in serum and urine chemistry. Likewise, AHE treatment decreases sensitive markers of oxidative stress and prevented DNA damages by enhancing antioxidant enzyme levels. DOX induction in rats also caused DNA fragmentation which was restored by AHE co-treatment. Moreover, the histological observations evidenced that AHE effectively rescued the kidney tissue from DOX interceded oxidative damage. Our results suggest that co-treatment of AHE markedly improve DOX-induced deleterious effects in a dose-dependent manner. The potency of AHE co-treatment at 400 mg/kg dose is similar to silymarin. These outcomes revealed that A. hydaspica AHE extract might serve as a potential adjuvant that avoids DOX-induced nephrotoxicity.