Search results

Title: Pheromone homologs identified from the cloacal gland transcriptome of a male Ambystoma mexicanum
Creator: Hall, Kevin William
Date: 2015
Collection: Electronic Theses & Dissertations
Description: Pheromones play an important role in modifying vertebrate behavior, especially during courtship rituals (Wyatt 2014). The courtship behavior within the urodele group often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal glands of male Cynops pyrrhogaster (Kikuyama et al. 1995). Other proteinaceous pheromones...
Show morePheromones play an important role in modifying vertebrate behavior, especially during courtship rituals (Wyatt 2014). The courtship behavior within the urodele group often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal glands of male Cynops pyrrhogaster (Kikuyama et al. 1995). Other proteinaceous pheromones within the urodele group have been shown to elicit responses from females towards conspecific males (Yamamoto et al. 2000, Kikuyama et al. 2002, Houck et al. 2008). However, the presence and levels of expression of proteinaceous pheromones has yet to be identified within the family Ambystomatidae, which includes several important research models. Therefore, the objective of this research was to identify putative proteinaceous pheromones from male Ambystoma mexicanum, as well as their relative expression levels. The results indicate that A. mexicanum contains two different forms of sodefrin precursor-like factor (alpha and beta (Janssenswillen et al. 2015)), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The presence of these highly expressed proteinaceous pheromones may indicate that male A. mexicanum use several chemical cues to attract female conspecifics.
Show less

Title: Investigating fast folding of RNA pseudoknot VPK with an ultrafast microfluidic mixer
Creator: Meindl, Andreas John
Date: 2012
Collection: Electronic Theses & Dissertations
Description: Despite advances in understanding the theory behind RNA folding, ab initio prediction of the folding process has not been achieved yet. Given only the sequence information we still cannot tell the precise three-dimensional structure of neither RNA nor protein. Knowing the kinetics of folding we hope to learn more about the arrangement of secondary and tertiary structure.For that reason we investigated the folding process of RNA pseudoknot VPK with our microfluidic mixing device. VPK (variant...
Show moreDespite advances in understanding the theory behind RNA folding, ab initio prediction of the folding process has not been achieved yet. Given only the sequence information we still cannot tell the precise three-dimensional structure of neither RNA nor protein. Knowing the kinetics of folding we hope to learn more about the arrangement of secondary and tertiary structure.For that reason we investigated the folding process of RNA pseudoknot VPK with our microfluidic mixing device. VPK (variant pseudoknot) is a variant of the mouse mammary tumor virus (MMTV) pseudoknot and it was specifically designed to prevent the formation of alternative base pairings in the stem regions. Using two differently labeled samples, VPK-2AP and F-VPK, and high and low salt folding conditions, we analyzed the folding process and determined the different folding rates. Our results match very well with recently published findings, but they also raise the possible existence of folding transitions not seen in T-jump experiments. The measured folding times are in the range of 0.5 to several milliseconds.The folding process seems to have different pathways with one of the stems of the pseudoknot forming before, perhaps even initiating the folding of the other.
Show less