Differential effect of components of the extracellular matrix on differentiation and apoptosis

AbstractBackground: Epithelial cells are closely associated with a basement membrane, but the intimate relationships that affect growth, differentiation and survival remain enigmatic. We have previously reported that granulosa cells adjacent to the basement membrane of the ovarian follicle have a higher degree of differentiation compared with cells located distal to the basement membrane. By contrast, granulosa cells distal to the basement membrane are the first to undergo apoptosis during follicular atresia. Moreover, growth of granulosa cells in vitro on a naturally produced basement-membrane-like extracellular matrix (ECM) enhances progesterone production and the cellular response to gonadotropic hormones by an undefined mechanism.Results: To investigate the effect of the ECM on granulosa cell differentiation and death, primary granulosa cells were cultured on ECMs that lacked or contained bFGF (basic fibroblast growth factor). These otherwise identical ECMs were deposited by HR9 mouse endodermal cells, which do not synthesize bFGF, or by HR9 cells transfected with the bFGF gene. Both ECMs provided protection against apoptosis in serum-free medium, but only the bFGF-containing ECM maintained expression of the steroidogenic P450scc enzyme system and the production of progesterone. Moreover, culturing the cells on this ECM enhanced the expression of the 30 kDa steroid acute regulatory protein which plays a key role in steroid hormone biosynthesis. Laminin, but not fibronectin, was able to replace the ECM in protecting the cells from apoptosis; but not in maintaining steroidogenesis, whereas bFGF was able to enhance steroidogenesis without protecting the cells against apoptosis. Cells cultured on both ECMs or laminin had a well-developed actin cytoskeleton compared with cells cultured on non-coated dishes, which underwent apoptosis.Conclusions: Cellular responses to ECM are mediated by the combined action of macromolecular constituents and regulatory molecules, such as bFGF, that are sequestered and stored in the ECM. ECM or laminin protects against cell death by interacting with specific integrin receptors and maintaining a well-developed actin cytoskeleton. ECM-bound bFGF provides differentiation signals for granulosa cells, which are in intimate contact with the ECM. Thus, a clear distinction can be made between the survival activity and the differentiation stimulus exerted by the ECM on epithelial cells

Elevated Serum Thyroglobulin and Low Iodine Intake Are Associated with Nontoxic Nodular Goiter among Adults Living near the Eastern Mediterranean Coast

Background. Information about iodine intake is crucial for preventing thyroid diseases. Inadequate iodine intake can lead to thyroid diseases, including nontoxic nodular goiter (NNG). Objective. To estimate iodine intake and explore its correlation with thyroid diseases among Israeli adults living near the Mediterranean coast, where iodine-depleted desalinated water has become a major source of drinking water. Methods. Cross-sectional study of patients attending Barzilai Medical Center Ashkelon. Participants, who were classified as either NNG (n=17), hypothyroidism (n=14), or control (n=31), provided serum thyroglobulin (Tg) and completed a semiquantitative iodine food frequency questionnaire. Results. Elevated serum Tg values (Tg > 60 ng/mL) were significantly more prevalent in the NNG group than in the other groups (29% versus 7% and 0% for hypothyroidism and controls, resp., P<0.05). Mean estimated iodine intake was significantly lower in the NNG group (65±30 μg/d) than in controls (115±60 μg/d) (P<0.05) with intermediate intake in the hypothyroid group (73±38 μg/d). Conclusions. Elevated serum Tg values and low dietary iodine intake are associated with NNG among adult patients in Ashkelon District, Israel. Larger studies are needed in order to expand on these important initial findings

Uncovering tomato quantitative trait loci and candidate genes for fruit cuticular lipid composition using the Solanum pennellii introgression line population

[EN] The cuticle is a specialized cell wall layer that covers the outermost surface of the epidermal cells and has important implications for fruit permeability and pathogen susceptibility. In order to decipher the genetic control of tomato fruit cuticle composition, an introgression line (IL) population derived from a biparental cross between Solanum pennellii (LA0716) and the Solanum lycopersicum cultivar M82 was used to build a first map of associated quantitative trait loci (QTLs). A total of 24 cuticular waxes and 26 cutin monomers were determined. They showed changes associated with 18 genomic regions distributed in nine chromosomes affecting 19 ILs. Out of the five main fruit cuticular components described for the wild species S. pennellii, three of them were associated with IL3.4, IL12.1, and IL7.4.1, causing an increase in n-alkanes (>= C-30), a decrease in amyrin content, and a decrease in cuticle thickness of similar to 50%, respectively. Moreover, we also found a QTL associated with increased levels of amyrins in IL3.4. In addition, we propose some candidate genes on the basis of their differential gene expression and single nucleotide polymorphism variability between the introgressed and the recurrent alleles, which will be the subjects of further investigation.Research at the IBMCP was supported by the Spanish Ministry of Education and Culture (BIO2013-42193-R) and H2020 TRADITOM (634561). AA, AG, and J-PF-M thank COST FA1106 Quality Fruit for STSM and networking activities. This work was supported by the Israel Science Foundation (ISF) personal grant to AA (grant no. 646/11). We would like to thank the Adelis Foundation, the Leona M. and Harry B. Helmsley Charitable Trust, the Jeanne and Joseph Nissim Foundation for Life Sciences, Tom and Sondra Rykoff Family Foundation Research, and the Raymond Burton Plant Genome Research Fund for supporting AA's laboratory activity. AA is the incumbent of the Peter J. Cohn Professorial Chair. We are very grateful to Prof. Dani Zamir for providing us the S. pennellii IL collection and to Prof. Antonio Heredia for his valuable advice in preparing the manuscript for publication. We would like to acknowledge the help offered by the Electron Microscopy Unit at the WIS (Israel) for the TEM sample preparation and imaging, especially Elena Kartvelishvily, Eugenia Klein, and Eyal Shimoni. Finally, we would also like to thank Calanit Raanan and Tamara Berkutzki (Department of Veterinary Resources, WIS) for their help in tissue fixation and embedding, as well as Hanna Levanony (Department of Plant Sciences, WIS) for her help in tissue staining for the light microscopy studies.Fernández Moreno, JP.; Levy-Samoha, D.; Malitsky, S.; Monforte Gilabert, AJ.; Orzáez Calatayud, DV.; Aharoni, A.; Granell Richart, A. (2017). Uncovering tomato quantitative trait loci and candidate genes for fruit cuticular lipid composition using the Solanum pennellii introgression line population. Journal of Experimental Botany. 68(11):2703-2716. https://doi.org/10.1093/jxb/erx134S27032716681

Fruit-Surface Flavonoid Accumulation in Tomato Is Controlled by a SlMYB12-Regulated Transcriptional Network

The cuticle covering plants' aerial surfaces is a unique structure that plays a key role in organ development and protection against diverse stress conditions. A detailed analysis of the tomato colorless-peel y mutant was carried out in the framework of studying the outer surface of reproductive organs. The y mutant peel lacks the yellow flavonoid pigment naringenin chalcone, which has been suggested to influence the characteristics and function of the cuticular layer. Large-scale metabolic and transcript profiling revealed broad effects on both primary and secondary metabolism, related mostly to the biosynthesis of phenylpropanoids, particularly flavonoids. These were not restricted to the fruit or to a specific stage of its development and indicated that the y mutant phenotype is due to a mutation in a regulatory gene. Indeed, expression analyses specified three R2R3-MYB–type transcription factors that were significantly down-regulated in the y mutant fruit peel. One of these, SlMYB12, was mapped to the genomic region on tomato chromosome 1 previously shown to harbor the y mutation. Identification of an additional mutant allele that co-segregates with the colorless-peel trait, specific down-regulation of SlMYB12 and rescue of the y phenotype by overexpression of SlMYB12 on the mutant background, confirmed that a lesion in this regulator underlies the y phenotype. Hence, this work provides novel insight to the study of fleshy fruit cuticular structure and paves the way for the elucidation of the regulatory network that controls flavonoid accumulation in tomato fruit cuticle