Transient appearance ofStrongylocentrotus purpuratus Otx in micromere nuclei: Cytoplasmic retention of SpOtx possibly mediated through an α-actinin interaction

2008

359

532

“…A third micromere-specific anisotropy is the precocious nuclearization in fourth-cleavage micromeres of another maternal transcription factor, Otx (ref. 29 and Fig. S4).…”

Section: The Genomic Program For Initial Specification Of the Micromerementioning

confidence: 96%

“…2 A. They are four essential regulators of downstream micromere lineage function: alx1 (29), ets1 (9,33), tbr (34,35), and tel (9), plus SoxC, which in this lineage plays no role as it turns itself off shortly after activation.…”

Section: The Genomic Program For Initial Specification Of the Micromerementioning

confidence: 99%

Global regulatory logic for specification of an embryonic cell lineage

Oliveri

2008

359

532

“…Two of the spatially specific inputs into the pmar1 cis-regulatory system appear to be ␤-catenin͞Tcf and Otx. The latter is a transcription factor localized in fourth-cleavage micromere nuclei, as is ␤-catenin (11,21). At the bottom of the lavender domain of Fig.…”

Section: Brief Overview Of the Grn For Specification Of Endomesoderm mentioning

confidence: 99%

Regulatory gene networks and the properties of the developmental process

McClay²,

Hood³

2003

205

124

Genomic instructions for development are encoded in arrays of regulatory DNA. These specify large networks of interactions among genes producing transcription factors and signaling components. The architecture of such networks both explains and predicts developmental phenomenology. Although network analysis is yet in its early stages, some fundamental commonalities are already emerging. Two such are the use of multigenic feedback loops to ensure the progressivity of developmental regulatory states and the prevalence of repressive regulatory interactions in spatial control processes. Gene regulatory networks make it possible to explain the process of development in causal terms and eventually will enable the redesign of developmental regulatory circuitry to achieve different outcomes.

“…This gene is activated immediately upon the birth of the fourth cleavage micromeres in response to two maternal transcriptional inputs at this stage confined to these cells (2,3). Perturbation experiments showed that these are Otx, a transcription factor nuclearized in the fourth cleavage micromeres, but later in other cells as well (4), and maternal ␤-catenin, which is nuclearized downstream of a maternal anisotropy in activated Dishevelled protein, tethered at the vegetal pole of the egg (5, 6). As described earlier (1,7,8), pmar1 transcription activates a double-negative logic gate, which accounts for the institution of the whole downstream skeletogenic regulatory state, formulated by transcription of a specific set of regulatory and signaling genes.…”

mentioning

confidence: 99%

“…Nuclear Otx also becomes widely available (4), and yet our pmar1 construct, like the endogenous pmar1 gene, continues to be expressed only in SM. Fig.…”

mentioning

confidence: 99%

Regulative recovery in the sea urchin embryo and the stabilizing role of fail-safe gene network wiring

Smith

2009

Design features that ensure reproducible and invariant embryonic processes are major characteristics of current gene regulatory network models. New cis-regulatory studies on a gene regulatory network subcircuit activated early in the development of the sea urchin embryo reveal a sequence of encoded ''fail-safe'' regulatory devices. These ensure the maintenance of fate separation between skeletogenic and nonskeletogenic mesoderm lineages. An unexpected consequence of the network design revealed in the course of these experiments is that it enables the embryo to ''recover'' from regulatory interference that has catastrophic effects if this feature is disarmed. A reengineered regulatory system inserted into the embryo was used to prove how this system operates in vivo. Genomically encoded backup control circuitry thus provides the mechanism underlying a specific example of the regulative development for which the sea urchin embryo has long been famous.gene regulatory ͉ embryonic development ͉ regulatory subcircuit topology ͉ pmar/hesC