Birthdating studies

Current atmospheric C14 is about twice the level it was before the 1950s.

First author Kristy Spalding and colleagues capitalized on this relatively rapid decline in C14 to develop their dating method.

For instance, loss of PROP1, which is a homeodomain containing transcription factor, can result in an absence of growth hormone (GH), thyroid stimulating hormone (TSH), prolactin (PRL), luteinizing hormone (LH), and progressive loss of adrenocorticotrophic hormone (ACTH) in humans.

Mice containing null mutations in Prop1 also display a similar phenotype (Davis et al 2010). Davis, SW; Ellsworth, BS; Peréz-Millan, MI; Gergics, P; Schade, V; Foyouzi, N; Brinkmeier, ML; Mortensen, AH; Camper, SA. Pituitary gland development and disease: from stem cell to hormone production. Pérez-Millán, M; Zeidler, MG; Saunders, TL; Camper, SA; Davis, SW. Efficient, specific, developmentally appropriate cre-mediated recombination in anterior pituitary gonadotropes and thyrotropes.

One current project focuses on the morphogenesis of the pituitary gland, especially how signaling factors such as Bmp, Fgf, Wnt, and Shh contribute to the proper size, shape, and location of the pituitary gland. Embryonic Development of the Deer Mouse, Peromyscus maniculatus.

A seond project seeks to understand how the five horomone secreting cell types of the pituitary anterior lobe are specified and what signaling factors are necessary for their formation.

Morphological criteria have been established that distinguish nine types of cone bipolar cells and one type of rod bipolar cell in mouse and rat.

While anatomical and physiological aspects of bipolar types have been actively studied, little is known about the sequence of events that leads to bipolar cell type specification and the potential relationship this process may have with synapse formation in the outer plexiform layer.

Lpar1-GFP cells are preferentially generated on E11.5, whereas Cplx3 or Nurr1-positive cells are equally generated during the 2-day peak of subplate neurogenesis (E11.5–E12.5). Subplate neurons are recognized to be important players in cortical development and maturation, with distinct roles at different developmental ages (Kanold and Luhmann 2010). Robertson (2000) described somatostatin, neuropeptide Y, and acetylcholine esterase as functional markers of the embryonic rat subplate; yet, none of these distinguishes the subplate layer from the overlying cortical plate in postnatal (P21) brains.methodologies in rat and mouse retina, we have demonstrated that there are distinct waves of genesis of the two major bipolar cell types, with cone bipolar genesis preceding rod bipolar genesis.These waves of bipolar genesis correspond to the order of genesis of the presynaptic photoreceptor cell types. The adult retina contains a complement of well-characterized neurons and glia in three cellular layers (outer nuclear, inner nuclear and ganglion cell layers) separated by two distinct plexiform layers (the inner and outer plexiform layers) containing cellular processes and synapses [].However, all 4 markers overlap in their expression pattern to varying degrees. More in agreement with the latter, there are also reports of persistent immunohistochemical or in situ hybridization labeling of the postnatal and adult subplate layer (Arimatsu et al. Depending on the mediolateral position, cells within the subplate layer were primarily generated at E11 and E12 (plug date = E1), with a few more contributed by E13 divisions.Here we demonstrate with bromodeoxyuridine birthdating that cells labeled with any 1 of these molecular subplate markers are indeed generated at E11.5 or E12.5 in the mouse. In contrast to their many and well-characterized functions, there are conflicting reports of significant cell death during the early postnatal period (Price et al. In this study, we determined the distribution of cells in the P1 mouse cortex that were born between E10.5 and E13.5 and, in particular, show that there is continuous addition of cells to the subplate zone and underlying WM during this 72 h period for the NIHS mice used in this study.