Publications by authors named "Gil-Jung Kim"

The sea cucumber, , is one of the most valuable aquatic species. The color of body wall and appearance are important for the value of sea cucumbers. To examine expression pattern of (), (), and (), previously reported as differently expressed genes during the pigmentation of sea cucumber, we analyzed the temporal profiles of , , and mRNAs in LED-exposed and light-shielded .

View Article and Find Full Text PDF

The ascidian (sea peach), a marine invertebrate, belongs to the same genus of the phylum Chordata along with the ascidian (sea pineapple), which is one of the model animals in the field of developmental biology. The characteristics of development and reproduction of are not yet known in detail. In order to find out the spawning period of , we investigated development of the gonads during the annual reproductive cycle.

View Article and Find Full Text PDF

Ascidian embryos have become an important model for embryological studies, offering a simple example for mechanisms of cytoplasmic components segregation. It is a well-known example that the asymmetric segregation of mitochondria into muscle lineage cells occurs during ascidian embryogenesis. However, it is still unclear which signaling pathway is involved in this process.

View Article and Find Full Text PDF

We report a droplet-based microfluidic immunosensor for the rapid and accurate detection of melamine, an organic base that has been implicated in widescale adulteration of food products such as milk. Our melamine assay is based on the competitive reaction between native melamine and a melamine-fluorescein isothiocyanate (FITC) conjugate against an anti-hapten antibody. The adoption of fluorescence polarization, allows the quantification of melamine in a more direct and rapid manner than established heterogeneous methods based on liquid chromatography, mass spectrometry, and enzyme-linked immunosorbent assay (ELISA).

View Article and Find Full Text PDF

Herein, we describe for the first time the integration of pneumatic micro-pumps with droplet-based microfluidic systems as basic platform for the rapid detection and quantitation of biomarkers. Specifically, we combine this microfluidic platform with fluorescence polarization detection to identify and quantify the potent blood vessel inducing protein bovine angiogenin within cow's milk in high-throughput. The droplet-based fluorescence polarization immunoassay is successful in accurately determining the concentration (4.

View Article and Find Full Text PDF

FGF9/16/20 signaling pathway specify the developmental fates of notochord, mesenchyme, and neural cells in ascidian embryos. Although a conserved Ras/MEK/Erk/Ets pathway is known to be involved in this signaling, the detailed mechanisms of regulation of FGF signaling pathway have remained largely elusive. In this study, we have isolated Hr-Erf, an ascidian orthologue of vertebrate Erf, to elucidate interactions of transcription factors involved in FGF signaling of the ascidian embryo.

View Article and Find Full Text PDF

Notch signaling plays fundamental roles in various animal development. It has been suggested that Hr-Notch, a Notch homologue in the ascidian Halocynthia roretzi, is involved in the formation of peripheral neurons by suppressing the neural fates and promoting the epidermal differentiation. However, roles of Notch signaling remain controversial in the formation of nervous system in ascidian embryos.

View Article and Find Full Text PDF

A forward genetic screen in the ascidian Ciona intestinalis identified a mutant line (frimousse) with a profound disruption in neural plate development. In embryos with the frimousse mutation, the anteriormost neural plate cells, which are products of an FGF induction at the blastula and gastrula stages, initially express neural plate-specific genes but fail to maintain the induced state and ultimately default to epidermis. The genetic lesion in the frimousse mutant lies within a connexin gene (cx-11) that is transiently expressed in the developing neural plate in a temporal window corresponding to the period of a-lineage neural induction.

View Article and Find Full Text PDF

There is widespread interest in defining factors and mechanisms that suppress the proliferation of cancer cells. Retinoic acid (RA) is a potent suppressor of mammary cancer and developmental embryonic cell proliferation. However, the molecular mechanisms by which 9-cis-RA signaling induces growth inhibition in RA-sensitive breast cancer and embryonic cells are not apparent.

View Article and Find Full Text PDF

The farnesoid X receptors (FXRs) are the major transcriptional regulators of bile salt synthesis in vertebrates. However, the structural conservation of invertebrate FXRs has only been studied for the major model organisms and studies on additional invertebrate FXRs are clearly required to obtain better resolution of FXR phylogeny and comparative developmental insights in chordates. In the present study, the cDNA encoding the farnesoid X receptor, HrFXR, was cloned from a marine invertebrate Halocynthia roretzi.

View Article and Find Full Text PDF

Mechanisms that regulate the number of cells constituting the body have remained largely elusive. We approached this issue in the ascidian, Halocynthia roretzi, which develops into a tadpole larva with a small number of cells. The embryonic cells divide 11 times on average from fertilization to hatching.

View Article and Find Full Text PDF
Article Synopsis
  • Researchers identified a new steroid receptor coactivator from the sea urchin species Strongylocentrotus nudus (SnSRC) using a specific protein bait in a yeast screening process.
  • SnSRC shares similar structural domains with other vertebrate SRCs, contains two functional interaction domains for nuclear receptors (NRs), and interacts with multiple hormone receptors.
  • Knockdown experiments indicate that SnSRC is crucial for early embryonic development, as its absence leads to significant developmental abnormalities in sea urchin embryos.
View Article and Find Full Text PDF

Estrogen receptor-related receptors (ERRs) were the first orphan nuclear receptors identified on the basis of their sequence similarity to the estrogen receptors. Although unique ERRs were found in some marine invertebrates, the molecular functions of these receptors are not well understood. In the present study, we identified three transcript variants of the tunicate Halocynthia roretzi ERR (Hr-ERR), varying in their 3' untranslated regions, and putatively encoding a unique receptor deriving from an ancestor protein common to vertebrate ERRalpha/beta/gamma.

View Article and Find Full Text PDF

We sequenced and characterized the complete mitochondrial genome of the Japanese fish tapeworm D. nihonkaiense. The genome is a circular-DNA molecule of 13607 bp (one nucleotide shorter than that of D.

View Article and Find Full Text PDF

Asymmetric cell division plays a fundamental role in generating various types of embryonic cell. In ascidian embryos, asymmetric cell divisions occur in the vegetal hemisphere in a manner similar to those found in Caenorhabditis elegans. Early divisions in embryos of both species involve inductive events on a single mother cell that result in production of daughters with different cell fates.

View Article and Find Full Text PDF