Genetic divergence among African and American cotton (Gossypium hirsutum L. race latifolium H.) cultivars and inbred lines through random amplification of polymorphic DNA (RAPD) markers.

Cotton (Gossypium spp.) is an important cash crop and the second largest source of textile fiber and edible oil throughout the world. This study was conducted to investigate the genetic divergence through random amplified polymorphism (RAPD) molecular markers among the introduced African and American cultivars and inbred lines of cotton (Gossypium hirsutum L. raça latifolium H.) in Mozambique. We used 24 RAPD primers that amplified a total of 166 bands, identifying 90.96% ofpolymorphism. The intra and inter group genetic variability quantification evidenced significant variability of 16.30% between the African and American groups. The highest genetic similarity was observed among the African commercial cotton cultivars, whereas American cultivars and inbred lines were considered the most dissimilar ones. The arithmetic complement of Jaccard, obtained with 151 RAPD molecular markers showed that African cultivars Albar BC853 and STAM 42 were the most similar, while the most dissimilar combinations were TAMCOT Sphinx and ISA 205 followed by TAMCOT Sphinx vs ALBAR BC853 and TAMCOT Sphinx vs REMU 40 combinations.Keywords: Molecular variance analysis, decamer primers, dissimilarity, Gossypium hirsutum, molecular markers

Methanethiosulfonate derivatives as ligands of STAT3-SH2 domain

It is well known that inflammatory conditions in selected organs increase the risk of cancer. Compounds of the inflammatory tumor microenvironment include leukocytes, cytokines, complement components, are orchestrated by transcription factors, such as STAT-3 (Signal Transducer and Activator of Transcription 3) and NF-kB. Therefore drugs able to inhibit one or both transcription factors could be useful tools to treat cancer disease. Two main approaches have been explored to inhibit STAT-3 signalling: \u2022 indirect, inhibiting the upstream tyrosine kinases that are responsible for STAT-3 activation or blocking factors such as JAK, Src, Bcr-Abl, FLT3 and EGFR that are involved in the activation of STAT-3 signalling. This kind of inhibition induces tumour-cell apoptosis but is poor selective. \u2022 direct, by interaction of small molecules with the protein. In this selective approach the starting point is the crystallographic structure of STAT-3 SH2 domain. S-methyl methanethiosulfonate, isolated from cauliflower has been shown to inhibit colon tumor incidence when administered to rats during the post-initiation phase of carcinogenesis [1]. Recently, a new methanethiosulfonate derivative of valproic acid (ACS33) was reported by some of us to show good in vitro antiproliferative activity and to inhibit in vivo the growth of PC3 in subcutaneous xenograft mice models [2]. Fig.1: Structures of the studied thiosulfonate hybrids. Since the influence of methanethiosulfonates on STAT-3 activity has not been yet studied, we decided to synthesize a set of thiosulfonate-drug hybrids (Fig.1) and to submit them and their parent compounds to the AlphaScreen-based assay, to investigate their ability to bind STAT-3 SH2 domain. Moreover, in order to check the selectivity of our molecules on STAT-3, other SH2-containing proteins, such as STAT-1, exhibiting a high degree of sequence homology to STAT-3, have also been tested. Results showed that most of the synthesized thiosulfonate-hybrids are able to strongly and selectively bind STAT-3 SH2 domain, whereas the parent drugs were completely devoid of this ability. Studies are ongoing to better define the profile of our new methanethiosulfonate derivatives as potential dual STAT-3/NFkB inhibitors. References 1. Reddy, B. S.; Kawamori, T.; Lubet, R.; Steele, V.; Kelloff, G.; Rao, C. V. Chemopreventive effect of S-methylmethane thiosulfonate and sulindac administered together during the promotion/progression stages of colon carcinogenesis Carcinogenesis 1999, 20, 1645-8. 2. Wedel S. A.; Sparatore A.; Del Soldato P.; Al-Batran S. E.; Atmaca A.; Juengel E.; Hudak L.; Jonas D.; Blaheta R. A. New histone deacetylase inhibitors as potential therapeutics tools for advanced prostate carcinoma. J. Cell. Mol Med 2008, 12, 2457-66

Monazite compositions in Licungo Pegmatite Field, Zambézia, Moçambique - pegmatites age and evolution

O presente trabalho contou com o apoio financeiro da Fundação Calouste Gulbenkian através do Programa de estímulo à investigação aos doutorandos dos países de língua oficial portuguesa (PALOP) e Timor Lesteinfo:eu-repo/semantics/publishedVersio