The Complex Interplay of TGF-β and Notch Signaling in the Pathogenesis of Fibrosis.

Fibrosis is a major medical challenge, as it leads to irreversible tissue remodeling and organ dysfunction. Its progression contributes significantly to morbidity and mortality worldwide, with limited therapeutic options available. Extensive research on the molecular mechanisms of fibrosis has revealed numerous factors and signaling pathways involved.

Early mesodermal expression of Hox genes in the polychaete Alitta virens (Annelida, Lophotrochozoa).

Hox genes are the key regulators of axial regionalization of bilaterian animals. However, their main function is fulfilled differently in the development of animals from different evolutionary branches. Early patterning of the developing embryos by Hox gene expression in the representatives of protostomes (arthropods, mollusks) starts in the ectodermal cells.

[Hox Genes and Animal Regeneration].

The concept of regeneration is intimately associated with ideas about positional information, that is, the distribution of various signals prescribing cells their location in an embryo or an adult organism. Hox genes are perfect candidates for the role of factors creating positional information. Their main function is thought to be regionalization of the embryo and the determination of the anterior/posterior (A/P) axis of the bilaterian body according to the rules of temporal and spatial colinearity.

Expression of Hox genes during regeneration of nereid polychaete Alitta (Nereis) virens (Annelida, Lophotrochozoa).

Background: Hox genes are the key determinants of different morphogenetic events in all bilaterian animals. These genes are probably responsible for the maintenance of regenerative capacities by providing positional information in the regenerating animal body. Polychaetes are well known for their ability to regenerate the posterior as well as the anterior part of the body.