Evolutionary Scenarios for the Specific Recognition of Non-homologous Endogenous Peptides by G Protein-Coupled Receptor Paralogs.

Several peptides interact with phylogenetically unrelated G protein-coupled receptors (GPCRs); similarly, orthologous GPCRs interact with distinct ligands. The neuropeptide Substance P (SP) activates both NK1R and another unrelated primate-specific GPCR, MRGPRX2. Furthermore, MRGPRX 1, a paralog of MRGPRX2, recognizes BAM8-22, which has no evolutionary relatedness to SP.

Comparative analysis of transcriptomic profiles among ascidians, zebrafish, and mice: Insights from tissue-specific gene expression.

Tissue/organ-specific genes (TSGs) are important not only for understanding organ development and function, but also for investigating the evolutionary lineages of organs in animals. Here, we investigate the TSGs of 9 adult tissues of an ascidian, Ciona intestinalis Type A (Ciona robusta), which lies in the important position of being the sister group of vertebrates. RNA-seq and qRT-PCR identified the Ciona TSGs in each tissue, and BLAST searches identified their homologs in zebrafish and mice.

A novel G protein-coupled receptor for starfish gonadotropic hormone, relaxin-like gonad-stimulating peptide.

Gonadotropic hormones play important regulatory roles in reproduction. Relaxin-like gonad-stimulating peptide (RGP) is a gonadotropin-like hormone in starfish. However, a receptor for RGP remains to be identified.

Bovine circumvallate taste buds: taste cell structure and immunoreactivity to alpha-gustducin.

The taste buds of bovine circumvallate papillae were investigated under light and electron microscopy both by histological and immunohistochemical methods. Taste buds existed in the inner epithelium of the trench of the papillae. Under electron microscopy, two types of taste cells, type I and type II, could be classified according to the existence of dense-cored vesicles and cytoplasmic density.