Pedro Sampaio

National Institute of Health Dr. Ricardo Jorge | INSA · Department of Health Promotion and Chronical Diseases

Internal organs are asymmetrically positioned inside the body. Embryonic motile cilia play an essential role in this process by generating a directional fluid flow inside the vertebrate left-right organizer. Detailed characterization of how fluid flow dynamics modulates laterality is lacking. We used zebrafish genetics to experimentally generate a...

In autosomal dominant polycystic kidney disease (ADPKD), cyst inflation and continuous enlargement are associated with marked transepithelial ion and fluid secretion into the cyst lumen via cystic fibrosis transmembrane conductance regulator (CFTR). Indeed, the inhibition or degradation of CFTR prevents the fluid accumulation within cysts. The in v...

Evaluation of ciliary beat frequency (CBF) performed by high-speed videomicroscopy analysis (HVMA) is one of the techniques required for the correct diagnosis of primary ciliary dyskinesia (PCD). Currently, due to lack of open-source software, this technique is widely performed by visually counting the ciliary beatings per a given time-window. Our...

Humans and other vertebrates define body axis left-right asymmetry in the early stages of embryo development. The mechanism behind left-right establishment is not fully understood. Although it is known that the symmetry break occurs in a dedicated organ called the left-right organizer (LRO) and involves motile cilia generating fluid flow therein, i...

Zebrafish is a vertebrate teleost widely used in many areas of research. As embryos, they develop quickly and provide unique opportunities for research studies owing to their transparency for at least 48 h post fertilization. Zebrafish have many ciliated organs that include primary cilia as well as motile cilia. Using zebrafish as an animal model h...

Primary ciliary dyskinesia (PCD) is genetically and clinically heterogeneous. CCNO mutations are associated with chronic destructive lung disease and were first described in 2014. Early reports suggest that CCNO is mutated more frequently than expected, however, these are considered rare. We report on three eleven-year-old children with PCD due to...

The left-right (LR) field recognizes the importance of the mechanism involving the calcium permeable channel Polycystin-2. However, whether the early LR symmetry breaking mechanism is exclusively via Polycystin-2 has not been tested. For that purpose, we need to be able to isolate the effects of decreasing the levels of Pkd2 protein from any eventu...

About 1% of all newborns are affected by congenital heart disease (CHD). Recent findings identify aberrantly functioning cilia as a possible source for CHD. Faulty cilia also prevent the development of proper left-right asymmetry and cause heterotaxy, the incorrect placement of visceral organs. Intriguingly, signaling cascades such as mTor that inf...

GO annotation for gene groups obtained with the R package clusterProfiler.

Contains data on foxj1a gene expression by in situ hybridization and by qPCR.

Contains data about the number of motile and immotile cilia from single embryos along development from 3 ss to 8 ss (n = 4).

Contains data on the relative expression levels of several genes by quantitative PCR. It shows comparisons between dld−/− mutants and wild type embryos.

Contains data from the native particles tracked to generate the flow maps on Figure 2. Shows the evaluation of the motile and immotile cilia by transmitted light microscopy with a high speed video-camera and the corresponding cilia beat frequency for the motile cilia.

Contains data on her12 positive DFC number and its anterior posterior location within the DFC cluster.

Microarray data. Excel file that contains Table S1a - List of 706 genes with significantly altered transcription. This list contains 706 genes with a fold change in transcription higher than 2, in the DFCs from dld−/− mutant zebrafish embryos. Table S1b – List of motility associated genes from the Table S1a that have been associated with cilia in t...

Contains the R script for creating and analysing the flow maps.

Provides data on the coordinates of immotile cilia denoting posterior to anterior transitions.

Relative expression levels of dnah7, her12, dnah9, rfx4 and foxj1a by qPCR for different Notch signalling manipulations. Contains data and statistical tests for the number of motile cilia per KV.

Provides data on flow speed and CBF upon her12 overexpression. Shows data for dand5 pattern and organ situs scoring per embryo. Shows the data for cilia length measurements in 3D and the evaluation of motile and immotile cilia localization according to the anterior – posterior axis of each stack of images.

Foxj1a is necessary and sufficient to specify motile cilia. Using transcriptional studies and slow-scan two-photon live imaging capable of identifying the number of motile and immotile cilia, we now established that the final number of motile cilia depends on Notch signalling (NS). We found that despite all left-right organizer (LRO) cells express...

Reduction in the length of motile cilia in the zebrafish left–right organizer (LRO), also known as Kupffer's vesicle, has a large impact on left–right development. Here we demonstrate through genetic overexpression in zebrafish embryos and mathematical modelling that the impact of increased motile cilia length in embryonic LRO fluid flow is milder...