The purple sea urchin Strongylocentrotus purpuratus has been used for over 150 years as a model organism in developmental biology. Using this model species, scientists have been able to describe, in detail, the mechanisms of cell cycle control and cell adhesion, fertilization, calcium signaling, cell differentiation, and death. Massive parallel sequencing of the sea urchin genome enabled the deciphering of the main components of gene regulatory networks during the activation of embryonic signaling pathways. This knowledge helped to extrapolate aberrations in somatic cells that may lead to diseases, including cancer in humans. Furthermore, since many, if not all, developmental signaling pathways were shown to be controlled by non-coding RNAs (ncRNAs), the sea urchin organism represents an attractive experimental model. In this review, we discuss the main discoveries in the genetics, genomics, and transcriptomics of sea urchins during embryogenesis with the main focus on the role of ncRNAs. This information may be useful for comparative studies between different organisms, and may help identify new regulatory networks controlled by ncRNAs.

Aurelia aurita has a complex life cycle that consists of several stages including alternating generations of medusa and polyps, huge sexual, and tiny asexual stages. Cnidarian is thought to possess two tissue layers: endoderm (gastroderm) and ectoderm, which are separated by mesoglea in medusa. The determination of the composition of the A. aurita jellyfish mesoglea was performed. New protein "mesoglein" was determined as one of the main components of mesoglea. Mesoglein is synthesized by mesogleal cells (Mc), which are populated A. aurita mesoglea as a high molecular mass precursor. Mc are involved in the formation of noncollagenous "elastic" fibers. Deduced amino acid sequence of mesoglein contains Zona Pellucida (ZP) domain and Delta/Serrate/Lag-2 domain. According to reverse transcription PCR, mesoglein is expressed in the mature medusa exclusively in the Mc. The sperm binding to the ZP is particularly important for successful fertilization. Antibodies against mesoglein stain the plate in the place of contact of germinal epithelium and oocyte. The structure found was named the "contact plate." The contact plate could be the precursor of the ZP. All our data suggest that Mc and, probably, the whole mesoglea originate from the epidermis (ectoderm). Computer search for mesoglein relatives reveals Nematostella and Trichoplax proteins as predicted ORFs, indicating that ZP proteins are quite ancient purchase in the evolution.

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Honey bees are model organisms for microbiota research. Gut microbiomes are very interesting for surveys due to their simple structure and relationship with hive production. Long-term studies reveal the gut microbiota patterns of various hive members, as well as the functions, sources, and interactions of the majority of its bacteria. But the fungal non-pathogenic part of gut microbiota is almost unexplored, likewise some other related microbiota. Honey bees, as superorganisms, interact with their own microorganisms, the microbial communities of food stores, hive surfaces, and other environments. Understanding microbiota diversity, its transition ways, and hive niche colonization control are necessary for understanding any separate microbiota niche because of their interplay. The long coevolution of bees with the microorganisms populating these niches makes these systems co-dependent, integrated, and stable. Interaction with the environment, hive, and other bees determines caste lifestyle as well as individual microbiota. In this article, we bring together studies on the microbiota of the western honey bee. We show a possible relationship between caste determination and microbiota composition. And what is primary: caste differentiation or microbiota composition?