Heterogeneity and genomic loci of ubiquitous Cre reporter transgenes in zebrafish

The most-common strategy for zebrafish Cre/lox-mediated lineage labeling experiments combines ubiquitously expressed, lox-based Switch reporter transgenes with tissue-specific Cre or 4-OH-Tamoxifen-inducible CreERT2 driver lines. Although numerous Cre driver lines have been produced, only a few broadly expressed Switch reporters exist in zebrafish and their generation by random transgene integration has been challenging due to position-effect sensitivity of the lox-flanked recombination cassettes. Here, we compare commonly used Switch reporter lines for their recombination efficiency and reporter expression pattern during zebrafish development. Using different experimental setups, we show that ubi:Switch and hsp70l:Switch outperform current generations of two additional Switch reporters due to favorable transgene integration sites. Our comparisons also document preferential Cre-dependent recombination of ubi:Switch and hsp70l:Switch in distinct zebrafish tissues at early developmental stages. To investigate what genomic features may influence Cre accessibility and lox recombination efficiency in highly functional Switch lines, we mapped these transgenes and charted chromatin dynamics at their integration sites. Our data documents the heterogeneity among lox-based Switch transgenes towards informing suitable transgene selection for lineage labeling experiments. Our work further proposes that ubi:Switch and hsp70l:Switch define genomic integration sites suitable for universal transgene or switch reporter knock-in in zebrafish.

Download Full-text

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005161x ◽

1974 ◽

Vol 32 ◽

pp. 320-321

Author(s):

J. P. Revel

Keyword(s):

Developmental Stages ◽

Three Dimensional ◽

Cell Movement ◽

Cellular Interactions ◽

Serial Sections ◽

Cell Sheets ◽

Freeze Etching ◽

Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

Download Full-text

Widely separated multiple transgene integration sites in wheat chromosomes are brought together at interphase

The Plant Journal ◽

10.1046/j.1365-313x.2000.00908.x ◽

2000 ◽

Vol 24 (6) ◽

pp. 713-723 ◽

Cited By ~ 45

Author(s):

Rita Abranches ◽

Ana P. Santos ◽

Eva Wegel ◽

Sarah Williams ◽

Alexandra Castilho ◽

...

Keyword(s):

Transgene Integration ◽

Integration Sites

Download Full-text

Review of early developmental stages of trilobites and agnostids from the Barrandian area (Czech Republic)

Journal of the National Museum (Prague), Natural History Series ◽

10.2478/jzh-2018-0006 ◽

2017 ◽

Vol 186 (1) ◽

pp. 103-112

Author(s):

Lukáš Laibl ◽

Oldřich Fatka

Keyword(s):

Czech Republic ◽

Developmental Stages ◽

History Of Research ◽

Early Developmental Stages ◽

History Of ◽

Barrandian Area ◽

Early Developmental

This contribution briefly summarizes the history of research, modes of preservation and stratigraphic distribution of 51 trilobite and five agnostid taxa from the Barrandian area, for which the early developmental stages have been described.

Download Full-text

The Effect of an Anthropogenic Magnetic Field on the Early Developmental Stages of Fishes—A Review

International Journal of Molecular Sciences ◽

10.3390/ijms22031210 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1210

Author(s):

Krzysztof Formicki ◽

Agata Korzelecka-Orkisz ◽

Adam Tański

Keyword(s):

Magnetic Fields ◽

Developmental Stages ◽

Negative Influence ◽

Pigment Cells ◽

Egg Activation ◽

Industrial Equipment ◽

Positive Effects ◽

Early Developmental Stages ◽

Species Specific ◽

Early Developmental

The number of sources of anthropogenic magnetic and electromagnetic fields generated by various underwater facilities, industrial equipment, and transferring devices in aquatic environment is increasing. These have an effect on an array of fish life processes, but especially the early developmental stages. The magnitude of these effects depends on field strength and time of exposure and is species-specific. We review studies on the effect of magnetic fields on the course of embryogenesis, with special reference to survival, the size of the embryos, embryonic motor function, changes in pigment cells, respiration hatching, and directional reactions. We also describe the effect of magnetic fields on sperm motility and egg activation. Magnetic fields can exert positive effects, as in the case of the considerable extension of sperm capability of activation, or have a negative influence in the form of a disturbance in heart rate or developmental instability in inner ear organs.

Download Full-text

Wnt/β-catenin Pathway-Mediated PPARδ Expression during Embryonic Development Differentiation and Disease

International Journal of Molecular Sciences ◽

10.3390/ijms22041854 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1854

Author(s):

Tabinda Sidrat ◽

Zia-Ur Rehman ◽

Myeong-Don Joo ◽

Kyeong-Lim Lee ◽

Il-Keun Kong

Keyword(s):

Embryonic Development ◽

Transcriptional Activation ◽

Target Gene ◽

Developmental Stages ◽

Embryonic Stem ◽

Hereditary Diseases ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

Stem Cell Regulation ◽

Early Developmental

The Wnt/β-catenin signaling pathway plays a crucial role in early embryonic development. Wnt/β-catenin signaling is a major regulator of cell proliferation and keeps embryonic stem cells (ESCs) in the pluripotent state. Dysregulation of Wnt signaling in the early developmental stages causes several hereditary diseases that lead to embryonic abnormalities. Several other signaling molecules are directly or indirectly activated in response to Wnt/β-catenin stimulation. The crosstalk of these signaling factors either synergizes or opposes the transcriptional activation of β-catenin/Tcf4-mediated target gene expression. Recently, the crosstalk between the peroxisome proliferator-activated receptor delta (PPARδ), which belongs to the steroid superfamily, and Wnt/β-catenin signaling has been reported to take place during several aspects of embryonic development. However, numerous questions need to be answered regarding the function and regulation of PPARδ in coordination with the Wnt/β-catenin pathway. Here, we have summarized the functional activation of the PPARδ in co-ordination with the Wnt/β-catenin pathway during the regulation of several aspects of embryonic development, stem cell regulation and maintenance, as well as during the progression of several metabolic disorders.

Download Full-text

Mitochondrial Processes during Early Development of Dictyostelium discoideum: From Bioenergetic to Proteomic Studies

Genes ◽

10.3390/genes12050638 ◽

2021 ◽

Vol 12 (5) ◽

pp. 638

Author(s):

Monika Mazur ◽

Daria Wojciechowska ◽

Ewa Sitkiewicz ◽

Agata Malinowska ◽

Bianka Świderska ◽

...

Keyword(s):

Life Cycle ◽

Developmental Stages ◽

Coupling Efficiency ◽

Slime Mold ◽

Intact Cells ◽

Life Cycle Stages ◽

Early Developmental Stages ◽

Proteomic Study ◽

And Function ◽

Early Developmental

The slime mold Dictyostelium discoideum’s life cycle includes different unicellular and multicellular stages that provide a convenient model for research concerning intracellular and intercellular mechanisms influencing mitochondria’s structure and function. We aim to determine the differences between the mitochondria isolated from the slime mold regarding its early developmental stages induced by starvation, namely the unicellular (U), aggregation (A) and streams (S) stages, at the bioenergetic and proteome levels. We measured the oxygen consumption of intact cells using the Clarke electrode and observed a distinct decrease in mitochondrial coupling capacity for stage S cells and a decrease in mitochondrial coupling efficiency for stage A and S cells. We also found changes in spare respiratory capacity. We performed a wide comparative proteomic study. During the transition from the unicellular stage to the multicellular stage, important proteomic differences occurred in stages A and S relating to the proteins of the main mitochondrial functional groups, showing characteristic tendencies that could be associated with their ongoing adaptation to starvation following cell reprogramming during the switch to gluconeogenesis. We suggest that the main mitochondrial processes are downregulated during the early developmental stages, although this needs to be verified by extending analogous studies to the next slime mold life cycle stages.

Download Full-text