understanding-early-organogenesis-using-simplified-situ-hybridization

Understanding Early Organogenesis Using a Simplified <em>In Situ</em> Hybridization Protocol in <em>Xenopus</em>

Organogenesis is the study of how organs are specified and then acquire their specific shape and functions during development.  The Xenopuslaevis embryo ...

Hospital for Sick Children

Individual cell shape changes are essential for epithelial morphogenesis. A transcriptional network for epithelial cell shape change is emerging in Drosophila, but this area remains largely unexplored in vertebrates. The distinction is important as so far, key downstream effectors of cell shape change in Drosophila appear not to be conserved. Rather, Shroom3 has emerged as a central effector of epithelial morphogenesis in vertebrates, driving both actin- and microtubule-based cell shape changes. To date, the morphogenetic role of Shroom3 has been explored only in the neural epithelium, so the broad expression of this gene raises two important questions: what are the requirements for Shroom3 in non-neural tissues and what factors control Shroom3 transcription? Here, we show in Xenopus that Shroom3 is essential for cell shape changes and morphogenesis in the developing vertebrate gut and that Shroom3 transcription in the gut requires the Pitx1 transcription factor. Moreover, we show that Pitx proteins directly activate Shroom3 transcription, and we identify Pitx-responsive regulatory elements in the genomic DNA upstream of Shroom3. Finally, we show that ectopic expression of Pitx proteins is sufficient to induce Shroom3-dependent cytoskeletal reorganization and epithelial cell shape change. These data demonstrate new breadth to the requirements for Shroom3 in morphogenesis, and they also provide a cell-biological basis for the role of Pitx transcription factors in morphogenesis. More generally, these results provide a foundation for deciphering the transcriptional network that underlies epithelial cell shape change in developing vertebrates.

Direct activation of Shroom3 transcription by Pitx proteins drives epithelial morphogenesis in the developing gut.

To investigate differences in fertilization, clinical pregnancy, and miscarriage rates between men with a markedly high sperm DNA fragmentation index (DFI) (>50%) and those with low DFI (≤ 15%) in couples matched by female partner age and ovarian reserve as determined by antimüllerian hormone (AMH) level.

In vitro fertilization-intracytoplasmic sperm injection outcome in patients with a markedly high DNA fragmentation index (>50%).

To date, there is limited published data on same-sex male couples and single men using assisted reproduction treatment to build their families. The objective of this retrospective study was to better understand treatment considerations and outcomes for this population when using assisted reproduction treatment. A total of 37 same-sex male couples and eight single men (seven homosexual and one heterosexual) who attended the CReATe Fertility Centre for assisted reproduction services were studied. There was a 21-fold increase in the number of same-sex male couples and single men undergoing assisted reproduction treatment since 2003. The mean age was 46years (24-58). Twenty-eight couples (76%) chose to use spermatozoa from both partners to fertilize their donated oocytes. Most men (32 same-sex male couples and seven single men; 87%) obtained oocytes from an anonymous donor, whereas five couples and one single man (13%) had a known donor. Anonymous donors who were open to be contacted by the child after the age of 18 were selected by 67% of patients. Of all 25 deliveries, eight (32%) were sets of twins. All of the twins were half genetic siblings.

Stephanie A. Grover

Neurosciences and Mental Health

Hospital for Sick Children

Understanding Early Organogenesis Using a Simplified In Situ Hybridization Protocol in Xenopus

Stephanie A. Grover

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Neurosciences and Mental Health

Hospital for Sick Children

Understanding Early Organogenesis Using a Simplified In Situ Hybridization Protocol in Xenopus

Neurosciences and Mental Health