genesis
Plant lateral organs, such as leaves, have three primary axes of growth–proximal‐distal, medial‐‐lateral and adaxial‐abaxial (dorsal‐ventral). Although most leaves are planar, modified leaf forms, such as the bikeeled grass prophyll, can be found in nature. A detailed examination of normal prophyll development indicates that polarity is established differently in the keels than in other parts of the...
We have generated a mouse strain carrying a Cre‐ERT2 knock‐in allele at the Pax7 locus, the Pax7CE allele (Lepper et al., 2009, Nature 460:627–631). Combining Pax7CE and the R26RLacZ Cre reporter allele, here we describe temporal‐specific tamoxifen (tmx)‐inducible lineage tracing of embryonic Pax7‐expressing cells. In particular, we focus on the somitic lineage. Tmx‐inducible Cre activity directed...
Smooth muscle α actin (SMA) is a cytoskeletal protein expressed by mesenchymal and smooth muscle cell types, including mural cells (vascular smooth muscle cells and pericytes). Using Bacterial Artificial Chromosome (BAC) recombineering technology, we generated transgenic reporter mice that express a membrane localized cherry red fluorescent protein (mCherry), driven by the full‐length SMA promoter...
In caudal regions of the CNS, glycine constitutes the major inhibitory neurotransmitter. Here, we describe a mouse line that expresses Cre recombinase under the control of a BAC transgenic glycine transporter 2 (GlyT2) promoter fragment. Mating of GlyT2‐Cre mice with the Cre reporter mouse lines Rosa26/LacZ and Rosa26/YFP and analysis of double transgenic offsprings revealed strong transgene activity...
The central cell characterizes the angiosperm female gametophyte (embryo sac or megagametophyte) in that it directly participates in “double fertilization” to initiate endosperm development, a feature distinguishing angiosperm from all other plant taxa. Polygonum‐type central cell is a binucleate cell that, upon fertilization with one of the two sperm cells, forms triploid endosperm to nourish embryo...
NR4A nuclear receptors are a diverse group of orphan nuclear receptors with critical roles in regulating cell proliferation and cell differentiation. The ortholog of the NR4A nuclear receptor in Caenorhabditis elegans, NHR‐6, also has a role in cell proliferation and cell differentiation during organogenesis of the spermatheca. Here we show that NHR‐6 is able to bind the canonical NR4A monomer response...
Recently, a codon improved version of the Flpe site specific recombinase, termed Flpo, was reported as having greatly improved performance in mammalian cell applications. However, the degree of improvement could not be estimated because essentially no Flpe activity was observed. Here, we compare Flpe and Flpo accurately in a mammalian cell assay to estimate that Flpo is about five times more active...
We report the expression pattern and construction of a transgenic zebrafish line for a transcription factor involved in otic vesicle formation and skeletogenesis. The zinc finger transcription factor sp7 (formerly called osterix) is reported as a marker of osteoblasts. Using bacterial artificial chromosome (BAC)‐mediated transgenesis, we generated a zebrafish transgenic line for studying skeletal...
Focal adhesion kinase (FAK) is a critical mediator of matrix‐ and growth factor‐induced signaling during development. Myocyte‐restricted FAK deletion in mid‐gestation mice results in impaired ventricular septation and cardiac compaction. However, whether FAK regulates early cardiogenic steps remains unknown. To explore a role for FAK in multi‐chambered heart formation, we utilized anti‐sense morpholinos...
Hand1 regulates development of numerous tissues within the embryo, extraembryonic mesoderm, and trophectoderm. Systemic loss of Hand1 results in early embryonic lethality but the cause has remained unknown. To determine if Hand1 expression in extraembryonic mesoderm is essential for embryonic survival, Hand1 was conditionally deleted using the HoxB6‐Cre mouse line that expresses Cre in extraembryonic...
Adult transgenic zebrafish expressing eGFP under the control of the zinc finger transcription factor Sp7 gene, which is expressed in osteoblasts but not chondrocytes. In this line, eGFP expression recapitulates the endogenous gene pattern of expression in the otic placode, otic vesicle and developing skeletal structures. GFP‐positive cells are also observed in adult skeletal structures and in regenerating...
Appl1 (Adaptor protein containing pleckstrin homology [PH], phosphotyrosine binding [PTB], and Leucine zipper motifs) is an adaptor that participates in cell signaling by interacting with various signaling molecules including Akt, PI3‐kinase (PI3K), Rab5, adiponectin receptor, and TrkA. By using RNA knockdown technology, Appl1 has been implicated in zebrafish development and murine glucose metabolism...
We have previously generated a transgenic mouse strain (LSL‐TβRICA) containing a Cre‐inducible constitutively active TGFβ type I receptor (Bartholin et al., 2008, Genesis 46: 724–731). Transgene expression depends on the excision of a floxed‐transcriptional STOP (LSL, Lox‐STOP‐Lox) located upstream the TβRICA coding sequence. To evaluate the correct excision of the STOP signal in the presence of Cre‐recombinase,...
The Wnt‐signaling pathway is necessary in a variety of developmental processes and has been implicated in numerous pathologies. Wntless (Wls) binds to Wnt proteins and facilitates Wnt sorting and secretion. Conventional deletion of Wls results in early fetal lethality due to defects in body axis establishment. To gain insight into the function of Wls in later stages of development, we have generated...
Photoreceptor morphogenesis requires specific and coordinated localization of junctional markers at different stages of development. Here, we provide evidence that Drosophila Klp64D, a homolog of Kif3A motor subunit of the heterotrimeric Kinesin II complex, is essential for viability of developing photoreceptors and localization of junctional proteins. Genetic analysis of mutant clones shows that...
Genetic analysis of klp64D(kif3a homolog) function in the Drosophilapupal retina. The ommatidum on the left consists of wild‐type photoreceptors. The ommatidium on the right is a genetic mosaic containing wild‐type and mutant cells marked by green fluorescent protein. klp64Dmutant cells show mislocalization of adherens junction proteins, DE‐Cadherin and Armadillo (labeled by red and blue staining,...
NDN is one of several genes inactivated in Prader–Willi syndrome (PWS), a developmental disorder characterized by obesity, hypotonia, and developmental delay. We demonstrate that loss of Necdin in murine and human fibroblasts impairs polarity initiation through a Cdc42‐myosin‐dependent pathway, thereby reducing cell migration. We identified defective polarization in both primary neuron cultures and...