A functional screen for genes involved in Xenopus pronephros development

Abstract

In Xenopus, the pronephros is the functional larval kidney and consists of two identifiable components; the glomus, the pronephric tubules, which can be divided into four separate segments, based on marker gene expression. The simplicity of this organ, coupled with the fact that it displays the same basic organization and function as more complex mesonephros and metanephros, makes this an attractive model to study vertebrate kidney formation. In this study, we have performed a functional screen specifically to identify genes involved in pronephros development in Xenopus. Gain-of-function screens are performed by injecting mRNA pools made from a non-redundant X. tropicalis full-length plasmid cDNA library into X. laevis eggs, followed by sib-selection to identify the single clone that caused abnormal phenotypes in the pronephros. Out of 768 egg and gastrula stage cDNA clones, 31 genes, approximately 4% of the screened clones, affected pronephric marker expression examined by whole mount in situ hybridization or antibody staining. Most of the positive clones had clear expression patterns in pronephros and predicted/established functions highly likely to be involved in developmental processes. In order to carry out a more detailed study, we selected Sox7, Cpeb3, P53csv, Mecr and Dnajc15, which had highly specific expression patterns in the pronephric region. The over-expression of these five selected clones indicated that they caused pronephric abnormalities with different temporal and spatial effects. These results suggest that our strategy to identify novel genes involved in pronephros development was highly successful, and that this strategy is effective for the identification of novel genes involved in late developmental events.

17β‐Hydroxysteroid dehydrogenase type 8 and carbonyl reductase type 4 assemble as a ketoacyl reductase of human mitochondrial FAS

“…This disease is associated with multiple pathways and affects many tissues, such as kidney, liver, heart, and pancreas (38,39), the tissues where mitochondrial FAS II genes are highly expressed. Recent studies that showed dysregulation of Mecr caused abnormalities in Xenopus kidney development (40) are also consistent with the hypothesis that mitochondrial FAS is linked to kidney function.…”

Expression of Sox family genes in early lamprey development

“…In vertebrates, SoxFs are involved with vascular development and cardiogenesis, are expressed in structures such as the aortic arch, circulatory system, and pharyngeal arches in addition to parts of the CNS (Zhang et al, 2005; Kyuno et al, 2008). We isolated a single SoxF gene.…”

Copy Number Variation in Patients with Disorders of Sex Development Due to 46,XY Gonadal Dysgenesis

“…Dnajc15 has been suggested to be involved in pronephros development in Xenopus embryos [59], and Camk1d has been associated with type 2 diabetes [60]. Further analysis needs to conducted on these genes to define their potential role in gonad development.…”