Computer program sequence for analysis and summary of radioimmunoassay data

A sequence of three programs is described for efficient design and analysis of radio-immunoassays. The first program designs the assay; the second program analyzes all available data according to the organizational base provided by the first program; and the third program summarizes the results of several assays in either tabular or graphical form. The analysis program uses a logit response-log dose transformation to obtain a linear inhibition curve for all preparations assayed at multiple levels. The curves are subjected to a weithted, least squares, regression analysis. All curves are tested for linearity and parallelism with the curve chosen as standard, and a weighted mean potency estimate with error limits is computed for all preparations run at single or multiple dose levels with any degree of replication.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34088/1/0000369.pd

Molecular determinants of a competent bovine corpus luteum: first vs final wave dominant follicles

Reproductive management in cattle requires the synchrony of follicle development and oestrus before insemination. However, ovulation of follicles that have not undergone normal physiological maturation can lead to suboptimal luteal function. Here, we investigated the expression of a targeted set of 47 genes in (a) a first-wave vs final-wave dominant follicle (DF; the latter destined to ovulate spontaneously) and (b) 6-day-old corpora lutea (CLs) following either spontaneous ovulation or induced ovulation of a first-wave DF to ascertain their functional significance for competent CL development. Both the mass and progesterone-synthesising capacity of a CL formed following induced ovulation of a first-wave DF were impaired. These impaired CLs had reduced expression of steroidogenic enzymes (e.g. STAR and HSD3B1), luteotrophic receptors (LHCGR) and angiogenic regulators (e.g. VEGFA) and increased expression of BMP2 (linked to luteolysis). Relative to final-wave DFs, characteristic features of first-wave DFs included reduced oestradiol concentrations and a reduced oestradiol:progesterone ratio in the face of increased expression of key steroidogenic enzymes (i.e. CYP11A1, HSD3B1 and CYP19A1) in granulosa cells and reduced expression of the HDL receptor SCARB1 in thecal cells. Transcripts for further components of the TGF and IGF systems (e.g. INHA, INHBA, IGF2R and IGFBP2) varied between the first- and final-wave DFs. These results highlight the importance of hormones such as progesterone interacting with local components of both the TGF and IGF systems to affect the maturation of the ovulatory follicle and functional competency of the subsequent CL

Can luteal regression be reversed?

The corpus luteum is an endocrine gland whose limited lifespan is hormonally programmed. This debate article summarizes findings of our research group that challenge the principle that the end of function of the corpus luteum or luteal regression, once triggered, cannot be reversed. Overturning luteal regression by pharmacological manipulations may be of critical significance in designing strategies to improve fertility efficacy

Frequency and fate of microRNA editing in human brain

Primary transcripts of certain microRNA (miRNA) genes (pri-miRNAs) are subject to RNA editing that converts adenosine to inosine (A→I RNA editing). However, the frequency of the pri-miRNA editing and the fate of edited pri-miRNAs remain largely to be determined. Examination of already known pri-miRNA editing sites indicated that adenosine residues of the UAG triplet sequence might be edited more frequently. In the present study, therefore, we conducted a large-scale survey of human pri-miRNAs containing the UAG triplet sequence. By direct sequencing of RT–PCR products corresponding to pri-miRNAs, we examined 209 pri-miRNAs and identified 43 UAG and also 43 non-UAG editing sites in 47 pri-miRNAs, which were highly edited in human brain. In vitro miRNA processing assay using recombinant Drosha-DGCR8 and Dicer-TRBP (the human immuno deficiency virus transactivating response RNA-binding protein) complexes revealed that a majority of pri-miRNA editing is likely to interfere with the miRNA processing steps. In addition, four new edited miRNAs with altered seed sequences were identified by targeted cloning and sequencing of the miRNAs that would be processed from edited pri-miRNAs. Our studies predict that ∼16% of human pri-miRNAs are subject to A→I editing and, thus, miRNA editing could have a large impact on the miRNA-mediated gene silencing

Glucose Metabolism In Vivo in Four Commonly Used Inbred Mouse Strains

OBJECTIVE—To characterize differences in whole-body glucose metabolism between commonly used inbred mouse strains

Leptin Receptor Signaling and Action in the Central Nervous System

The increasing incidence of obesity in developed nations represents an ever‐growing challenge to health care by promoting diabetes and other diseases. The discovery of the hormone, leptin, a decade ago has facilitated the acquisition of new knowledge regarding the regulation of energy balance. A great deal remains to be discovered regarding the molecular and anatomic actions of leptin, however. Here, we discuss the mechanisms by which leptin activates intracellular signals, the roles that these signals play in leptin action in vivo, and sites of leptin action in vivo. Using “reporter” mice, in which LRb‐expressing (long form of the leptin receptor) neurons express the histological marker, β‐galactosidase, coupled with the detection of LRb‐mediated signal transducer and activator of transcription 3 signaling events, we identified LRb expression in neuronal populations both within and outside the hypothalamus. Understanding the regulation and physiological function of these myriad sites of central leptin action will be a crucial next step in the quest to understand mechanisms of leptin action and energy balance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93692/1/oby.2006.310.pd

Cell-Type Specific Expression of a Dominant Negative PKA Mutation in Mice

We employed the Cre recombinase/loxP system to create a mouse line in which PKA activity can be inhibited in any cell-type that expresses Cre recombinase. The mouse line carries a mutant Prkar1a allele encoding a glycine to aspartate substitution at position 324 in the carboxy-terminal cAMP-binding domain (site B). This mutation produces a dominant negative RIα regulatory subunit (RIαB) and leads to inhibition of PKA activity. Insertion of a loxP-flanked neomycin cassette in the intron preceding the site B mutation prevents expression of the mutant RIαB allele until Cre-mediated excision of the cassette occurs. Embryonic stem cells expressing RIαB demonstrated a reduction in PKA activity and inhibition of cAMP-responsive gene expression. Mice expressing RIαB in hepatocytes exhibited reduced PKA activity, normal fasting induced gene expression, and enhanced glucose disposal. Activation of the RIαB allele in vivo provides a novel system for the analysis of PKA function in physiology

Functional Consequences of the Human Leptin Receptor ( LEPR ) Q223R Transversion

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93715/1/oby.2008.489.pd