The isthmic organizer, which is located at the midbrain-hindbrain boundary, plays an essential role in development of the midbrain and anterior hindbrain. It has been shown that homeobox genes regulate establishment of the isthmic organizer, but the mechanism by which the organizer is maintained is not well understood. Here, we found that, in mice doubly mutant for the basic helix-loop-helix ge...

Neuroendocrine cells store and secrete bulk amounts of neuropeptides, and display morphological and molecular characteristics distinct from neurons signaling with classical neurotransmitters. In Drosophila the transcription factor Dimmed (Dimm), is a prime organizer of neuroendocrine capacity in a majority of the peptidergic neurons. These neurons display large cell bodies and extensive axon te...

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...

The regionalization of the neural tube along the anteroposterior axis is established through the action of patterning signals from the endomesoderm including the organizer. These signals set up a pre-pattern which is subsequently refined through local patterning events. The midbrain-hindbrain junction, or isthmus, is endowed with such an organizing activity. It is able to induce graded expressi...

The organizer is one of the earliest structures to be established during vertebrate development and is crucial to subsequent patterning of the embryo. We have previously shown that the SoxB1 transcription factor, Sox3, plays a central role as a transcriptional repressor of zebrafish organizer gene expression. Recent data suggest that Fgf signaling has a positive influence on organizer formation...

In this paper, we present algorithms for pattern matching, where either the pattern P or the text T can contain “don’t care” characters. If the pattern P contains don’t care characters, then we can solve the pattern matching problem in O(n +m + α) time, where α is the total number of occurrences of the component subpatterns. We also can handle online queries, given an O(n) preprocessing time, r...

A new diagnostic scheme is presented for ball bearing localized faults, which utilizes preprocessed time domain features based pattern recognition (PR). Vibration data is acquired from faulty bearings using a test rig, and the features are extracted from the data segments that are preprocessed prior to use in the fault classification process. The preprocessing involves smoothing of the features...

Brivanlou and Melton, 1992; Kessler and Melton, 1994; Schulte-Merker et al., 1994). At a later stage, signals Clare Hudson, Debbie Clements, Rosalind V. Friday, David Stott, and Hugh R. Woodland* originating in the dorsal organizer region (e.g., noggin, Department of Biological Sciences chordin, and nodal-related molecules) and local signalUniversity of Warwick ing molecules in the ventral and ...

We report an analysis of the tissue and molecular interplay involved in the early specification of the forebrain, and in particular telencephalic, regions of the Xenopus embryo. In dissection/recombination experiments, different parts of the organizer region were explanted at gastrula stage and tested for their inducing/patterning activities on either naive ectoderm or on midgastrula stage dors...