Biology subjects

Bloomekatz, J.

Publications and source records attributed to Bloomekatz, J..

3 recordsLinked to original sources

bioRxiv2025

A method for creating custom 3D-printed molds to facilitate zebrafish imaging studies, including of cardiac development.

Embryo mounting is one of the technical challenges researchers encounter when undertaking an imaging project. Embryos need to be oriented in a reproducible manner such that the tissue of interest is accessible to a microscope objective for the entire imaging period. To overcome this challenge researchers can embed embryos in viscous media or create specialized dishes and casts to hold embryos in a desired orientation during imaging. Here we describe a method for using a cheap stereolithographic (SLA) 3D-printer to manufacture re-usable molds that create agarose wells in which embryos can be mounted for imaging. These agarose wells provide a reliable means for orienting multiple embryos for imaging. This method includes a design framework that can be easily customized for a variety of tissues, organisms and imaging challenges. Using this method we have created molds for imaging cardiac development in zebrafish for both upright and inverted microscopes. By utilizing materials and equipment that are accessible this method allows researchers to easily create molds specific to their mounting needs. SUMMARYHere we describe a method that uses a cheap stereolithographic (SLA) 3D printer to create molds to facilitate the reproducible mounting of zebrafish embryos for imaging studies. Using this method, weve created molds for imaging cardiac morphogenesis in zebrafish embryos.

developmental biology↗

bioRxiv2023

The myocardium utilizes Pdgfra-PI3K signaling to steer towards the midline during heart tube formation

Coordinated cell movement is a fundamental process in organ formation. During heart development, bilateral myocardial precursors collectively move towards the midline (cardiac fusion) to form the primitive heart tube. Along with extrinsic influences such as the adjacent anterior endoderm which are known to be required for cardiac fusion, we previously showed that the platelet-derived growth factor receptor alpha (Pdgfra) is also required. However, an intrinsic mechanism that regulates myocardial movement remains to be elucidated. Here, we uncover an essential intrinsic role in the myocardium for the phosphoinositide 3-kinase (PI3K) intracellular signaling pathway in directing myocardial movement towards the midline. In vivo imaging reveals that in PI3K-inhibited zebrafish embryos myocardial movements are misdirected and slower, while midline-oriented dynamic myocardial membrane protrusions become unpolarized. Moreover, PI3K activity is dependent on and genetically interacts with Pdgfra to regulate myocardial movement. Together our findings reveal an intrinsic myocardial steering mechanism that responds to extrinsic cues during the initiation of cardiac development.

developmental biology↗

bioRxiv2021

Unveiling unexpected complexity and multipotentiality of early heart fields

Complex organs are composed of a multitude of specialized cell types which assemble to form functional biological structures. How these cell types are created and organized remains to be elucidated for many organs including the heart, the first organ to form during embryogenesis. Here, we show the ontogeny of mammalian mesoderm at high-resolution single cell and genetic lineage/clonal analyses, which revealed an unexpected complexity of the contribution and multi-potentiality of mesodermal progenitors to cardiac lineages creating distinct cell types forming specific regions of the heart. Single-cell transcriptomics of Mesp1 lineage-traced cells during embryogenesis and corresponding trajectory analyses uncovered unanticipated developmental relationships between these progenitors and lineages including two mesodermal progenitor sources contributing to the first heart field (FHF), an intraembryonic and a previously uncharacterized extraembryonic-related source, that produce distinct cardiac lineages creating the left ventricle. Lineage-tracing studies revealed that these extraembryonic-related FHF progenitors reside at the extraembryonic-intraembryonic interface in gastrulating embryos and generate cardiac cell types that form the epicardium and the dorsolateral regions of the left ventricle and atrioventricular canal myocardium. Clonal analyses further showed that these progenitors are multi-potent, creating not only cardiomyocytes and epicardial cell types but also extraembryonic mesoderm. Overall, these results reveal unsuspected multiregional origins of the heart fields, and provide new insights into the relationship between intraembryonic cardiac lineages and extraembryonic tissues and the associations between congenital heart disease and placental insufficiency anomalies.

developmental biology↗