Spemann's organizer plays an essential role in patterning the vertebrate embryo. During gastrulation, organizer cells involute and form the prechordal plate anteriorly and the notochord more posteriorly. The fate mapping and gene expression analyses in zebrafish presented in this study reveal that this anteroposterior polarity is already initiated in the organizer before gastrulation. Prechorda...

BACKGROUND AND AIMS Several diagnostic methods are being employed to detect benign and malignant lesions, one of which is silver nitrate staining for organizer regions. The number of nucleolar organizing regions (NORs) can be used to show the degree of cell activity or metabolism in pathologic lesions. This study was designed to evaluate NORs as determi-nants of precancerous and squamous cell c...

The 16th FASEB Science Research Conference on Ca2+ and Cell Function took place in Lisbon, Portugal, on June 12–17, 2016. Chaired by Stefan Feske (New York University, organizer) and Murali Prakriya (Northwestern University, co-organizer), it brought together over 130 scientists from North America, Europe, and Asia.

The neuroectoderm arises during gastrulation as a population of undifferentiated proliferating neuroepithelial cells. As development continues, neuroepithelial cells leave the cell cycle and differentiate into neurons and glia of the functioning central nervous system. What processes establish the spatial distribution of proliferating neuroepithelial cells? To investigate this question, zic2a w...

During gastrulation, diffusible "organizer" signals, including members of the TGFbeta Nodal subfamily, pattern dorsal mesoderm and the embryonic axes. Simultaneously, negative regulators of these signals, including the Nodal inhibitor Lefty, an atypical TGFbeta factor, are induced by Nodal. This suggests that Lefty-dependent modulation of organizer signaling might regulate dorsal mesoderm patte...

The organizer is established at the blastula stage of development, under the influence of a special region of cells known as the Nieuwkoop center in amphibians, where Vg1/activin-like signals overlap with activity of the Wnt-pathway. Despite differences in their mode of early development, a similar region can be identified in other vertebrates. It has widely been assumed that once the organizer...

The present study examined the impact of visualization and graphic organizers as pre-listening strategies on English as a foreign language (EFL) learners’ cognitive, behavioral, and emotional engagement and their listening comprehension. To do so, this study was carried out in three listening classes at Islamic Azad University of Mashhad. The participants included 80 junior EFL university stude...

The molecular nature of Spemann's organizer phenomenon has long attracted the attention of embryologists. goosecoid is a homeobox gene with a DNA-binding specificity similar to that of Drosophila bicoid. Xenopus goosecoid is expressed on the dorsal side of the embryo before the dorsal lip is formed. Cells expressing goosecoid are fated to become pharyngeal endoderm, head mesoderm and notochord....

Rehovot 76100 ganizer, positioned on the future dorsal side of the em-Israel bryo, can be viewed as an array of distinct secreted inhibitors that pattern the embryo by antagonizing the activity of ventralizing factors (BMPs and Wnts). Studies In 1924 Hans Spemann and Hilde Mangold carried out in Xenopus have uncovered an amazing diversity of in-an experiment that revolutionized the field of dev...