Transient retinoic acid signaling confers anterior-posterior polarity to the inner ear.

Retinoic acid induces a pattern of digits in anterior half wing buds that lack the zone of polarizing activity.

Wing buds whose posterior half is excised, develop into wings lacking distal structures. However, such experimentally generated preaxial half wing buds can be rescued by implanting a retinoic-acid-releasing bead at their anterior margin. The polarity of the pattern that originates from preaxial half wing buds is reversed. For example, instead of a 234 digit pattern typical for normal wings, the...

Retinoic acid regulates anterior–posterior patterning within the lateral plate mesoderm of Xenopus

The lateral plate mesoderm (LPM) lines the body cavities, gives rise to the heart and circulatory system and is responsible for patterning the underlying endoderm. We describe gene expression domains within the lateral plate mesoderm of the neurula stage Xenopus embryo that demonstrate a marked anterior posterior pattern in that tissue. FoxF1 and Nkx-2.5 are expressed in the anterior LPM, Hand1...

The Ups and Downs of Retinoic Acid Signaling in Early Inner Ear Development

Deficiency in vitamin A during human development can perturb a number of developmental processes, including cell proliferation, migration, and differentiation, and lead to congenital malformations. There is no de novo synthesis of vitamin A in the human embryo, thus in utero developing tissues are reliant on maternal retinol, which is converted intracellularly into a biologically active derivat...

The effect of Fibroblast Growth Factor-2(FGF-2) and retinoic acid on differentiation of mouse embryonic stem cells into neural cells

Introduction: Embryonic Stem (ES) cells as pluripotent cells derived from the inner cell mass of blastula can differentiate to neural cells in vitro and this property is valuable in studies of neurogenesis and in the generation of donor cells for transplantation. In this regard, the propose of this research, was the study of the role of two important factors in the development of neural syst...

All-trans Retinoic Acid Regulates the Balance of Treg-Th17 Cells through ERK and P38 Signaling Pathway