Biostratigraphy and paleontology of some conchostracan-bearing beds in southern Africa

The present field and laboratory study was undertaken in conjunction with a monograph being prepared on Gondwana estheriids. Detailed biostratigraphic reports are lacking on the southern African conchostracan-bearing beds. The available paleontological treatment ranges from mere mentions of certain fossils being present to spare systematics. During the summer of 1979 a limited exploration program was undertaken at localities in the Clarens Formation (Cave Sandstone) outcrop belt where conchostracans had been reported (Stockley 1947, Haughton 1924, and especially Ellenberger et al. 1964). In particular, sites at Siberia and Barkly Pass (both in the Republic of South Africa) and at Thabaneng and Mofoka's Store (both in Lesotho) were found to yield excellent new biostratigraphic and paleontological data. The exploration covered some 1500 square miles (2400km2 of the Clarens Formation (Cave Sandstone) outcrop belt (Text fig. 1). Conchostracan-bearing Cave Sandstone sites noted by Paul Ellenberger (1970) at Leloaleng, Masitisi, Mohaleshoek, Brakfontein and elsewhere were systematically explored. Because of the lack of precise locality data enabling one to pinpoint the fossiliferous bed(s) even an intensive search did not uncover the reported fossiliferous beds. Exploration of one of Ellenberger's localities at Wonderkop (RSA) was abandoned after a preliminary search due to time limitations. This site may yet prove productive.National Science Foundation, US

Jurassic conchostracans from Patagonia

24 p., 19 fig.http://paleo.ku.edu/contributions.htm

Lower Permian algal stromatolites from Kansas and Oklahoma

20 p., 10 fig.http://paleo.ku.edu/contributions.htm

Role of TMPRSS2-ERG Gene Fusion in Negative Regulation of PSMA Expression

Prostate specific membrane antigen (PSMA) is overexpressed in prostatic adenocarcinoma (CaP), and its expression is negatively regulated by androgen stimulation. However, it is still unclear which factors are involved in this downregulation. TMPRSS2-ERG fusion is the most common known gene rearrangement in prostate carcinoma. Androgen stimulation can increase expression of the TMPRSS2-ERG fusion in fusion positive prostate cancer cells. The purpose of this investigation is to determine whether PSMA expression can be regulated by the TMPRSS2-ERG gene fusion. We employed two PSMA positive cell lines: VCaP cells, which harbor TMPRSS2-ERG fusion, and LNCaP cells, which lack the fusion. After 24 hours of androgen treatment, TMPRSS2-ERG mRNA level was increased in VCaP cells. PSMA mRNA level was dramatically decreased in VCaP cells, while it only has moderate change in LNCaP cells. Treatment with the androgen antagonist flutamide partially restored PSMA expression in androgen-treated VCaP cells. Knocking down ERG by siRNA in VCaP cells enhances PSMA expression both in the presence and absence of synthetic androgen R1881. Overexpressing TMPRSS2-ERG fusions in LNCaP cells downregulated PSMA both in the presence or absence of R1881, while overexpressing wild type ERG did not. Using PSMA-based luciferase reporter assays, we found TMPRSS2-ERG fusion can inhibit PSMA activity at the transcriptional level. Our data indicated that downregulation of PSMA in androgen-treated VCaP cells appears partially mediated by TMPRSS2-ERG gene fusion