Molecular characterisation of the gene, LGALS13, and its putative involvement in pre-eclampsia
Year: 2009
Type: dissertation
Abstract: Pre-eclampsia is one of the most common hypertensive disorders of \npregnancy in South Africa. Presently, the only cure for pre-eclampsia is \ndelivery, which brings with it, additional complications. As an alternative, \nclinical management of this disorder relies on timely diagnosis. \nThe predictive biomarker, Placental Protein 13 (PP13), is currently used \nfor the early diagnosis of pre-eclampsia, in an ELISA-based diagnostic \nkit, developed by Diagnostic Technologies Limited (DTL)1. A decrease in \nserum PP13 levels has been reported during the first trimester of \npregnancy in women who later develop pre-eclampsia. The function of \nPP13 has not been fully elucidated and it is also not known whether the \nreduction in PP13 levels is a cause or an effect of the disease. The use \nof PP13 as a predictive biomarker for pre-eclampsia therefore warrants a \ncomprehensive study of this peptide and the encoding gene, LGALS13. \nThe aim of this study was firstly to characterise LGALS13 using a range \nof in silico tools. PP13 was found to be most homologous to the \npredicted protein product of a neighbouring “putative” gene, LOC148003. \nA gene conversion event between these two genes most likely underlies \nthe so-called “hotspot mutation” in LGALS13. Data also demonstrates \nthat the DelT mutation disrupts functionally and structurally important \nfeatures of the gene and peptide sequences. Through the analysis of the \nputative promoter region of LGALS13, the presence of a Stimulatory \nprotein-1 (Sp1) binding sequence element was predicted, which has \nimplications for regulation of LGALS13. \nSecondly, the study aimed to establish a study cohort for the \ninvestigation of the effect that the LGALS13 genotype has on the \nexpression of its mRNA and protein products. Serum, plasma and whole blood samples were collected and prepared from 316 pregnant women. \nPlacental tissue samples were obtained from a selected group of these \nsubjects for RNA extraction. Once the sampling on the two remaining \ntargeted deliveries has occurred, the collection of samples will be \nbatched and sent to DTL in Israel, for PP13 measurement. \nDNA was extracted from the whole blood samples obtained, and all \nstudy participants were genotyped for seven sequence variants within \nthe LGALS13 gene using (i) Multiphor Single Stranded Conformational \nPolymorphism and Heteroduplex (SSCP/HD) analysis, (ii) restriction \nenzyme analysis and (iii) DNA sequencing. The genotype data sets will \nbe compared with PP13 levels when they become available, and also \nwith clinical parameters, once the deliveries have all occurred and the \ndatabase is complete. \nThis study demonstrated the power of an in silico approach to direct the \nfocus of future experimental work. The newly established study cohort \nwill be used for prospective studies aiming at a better understanding of \nthe role which LGALS13 and PP13 play in the early prediction of preeclampsia.
Author: Alisa Postma
Language: English
Subfield: Obstetrics and Gynecology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W852995464