Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Animals

2012

Biology Faculty Publications

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

Toward The Beginning Of Time: Circadian Rhythms In Metabolism Precede Rhythms In Clock Gene Expression In Mouse Embryonic Stem Cells, Jiffin K. Paulose, Edmund B. Rucker Iii, Vincent M. Cassone Nov 2012

Toward The Beginning Of Time: Circadian Rhythms In Metabolism Precede Rhythms In Clock Gene Expression In Mouse Embryonic Stem Cells, Jiffin K. Paulose, Edmund B. Rucker Iii, Vincent M. Cassone

Biology Faculty Publications

The appearance, progression, and potential role for circadian rhythms during early development have previously focused mainly on the suprachiasmatic nucleus (SCN) and peri- and postnatal expression of canonical clock genes. More recently, gene expression studies in embryonic stem cells have shown that some clock genes are expressed in undifferentiated cells; however rhythmicity was only established when cells are directed toward a neural fate. These studies also concluded that a functional clock is not present in ESCs, based solely on their gene expression. The null hypothesis underlying the present study is that embryonic stem cells become rhythmic in both clock gene …


Skin Regeneration In Adult Axolotls: A Blueprint For Scar-Free Healing In Vertebrates, Ashley W. Seifert, James R. Monaghan, S. Randal Voss, Malcolm Maden Apr 2012

Skin Regeneration In Adult Axolotls: A Blueprint For Scar-Free Healing In Vertebrates, Ashley W. Seifert, James R. Monaghan, S. Randal Voss, Malcolm Maden

Biology Faculty Publications

While considerable progress has been made towards understanding the complex processes and pathways that regulate human wound healing, regenerative medicine has been unable to develop therapies that coax the natural wound environment to heal scar-free. The inability to induce perfect skin regeneration stems partly from our limited understanding of how scar-free healing occurs in a natural setting. Here we have investigated the wound repair process in adult axolotls and demonstrate that they are capable of perfectly repairing full thickness excisional wounds made on the flank. In the context of mammalian wound repair, our findings reveal a substantial reduction in hemostasis, …


Environmentally Realistic Exposure To The Herbicide Atrazine Alters Some Sexually Selected Traits In Male Guppies, Kausalya Shenoy Feb 2012

Environmentally Realistic Exposure To The Herbicide Atrazine Alters Some Sexually Selected Traits In Male Guppies, Kausalya Shenoy

Biology Faculty Publications

Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments) and the …