Vertebrate Vitellogenin Gene Duplication in Relation to the “3R Hypothesis”: Correlation to the Pelagic Egg and the Oceanic Radiation of Teleosts

The spiny ray-finned teleost fishes (Acanthomorpha) are the most successful group of vertebrates in terms of species diversity. Their meteoric radiation and speciation in the oceans during the late Cretaceous and Eocene epoch is unprecedented in vertebrate history, occurring in one third of the time for similar diversity to appear in the birds and mammals. The success of marine teleosts is even more remarkable considering their long freshwater ancestry, since it implies solving major physiological challenges when freely broadcasting their eggs in the hyper-osmotic conditions of seawater. Most extant marine teleosts spawn highly hydrated pelagic eggs, due to differential proteolysis of vitellogenin (Vtg)-derived yolk proteins. The maturational degradation of Vtg involves depolymerization of mainly the lipovitellin heavy chain (LvH) of one form of Vtg to generate a large pool of free amino acids (FAA 150–200 mM). This organic osmolyte pool drives hydration of the ooctye while still protected within the maternal ovary. In the present contribution, we have used Bayesian analysis to examine the evolution of vertebrate Vtg genes in relation to the “3R hypothesis” of whole genome duplication (WGD) and the functional end points of LvH degradation during oocyte maturation. We find that teleost Vtgs have experienced a post-R3 lineage-specific gene duplication to form paralogous clusters that correlate to the pelagic and benthic character of the eggs. Neo-functionalization allowed one paralogue to be proteolyzed to FAA driving hydration of the maturing oocytes, which pre-adapts them to the marine environment and causes them to float. The timing of these events matches the appearance of the Acanthomorpha in the fossil record. We discuss the significance of these adaptations in relation to ancestral physiological features, and propose that the neo-functionalization of duplicated Vtg genes was a key event in the evolution and success of the teleosts in the oceanic environment

Selection acting on genomes

C. K. is supported by a grant of the Vienna Science and Technology Fund (WWTF—MA016-061). M. A. receives funding from the Swiss National Science Foundation (grant 31003A_176316).Populations evolve as mutations arise in individual organisms and, through hereditary transmission, may become “fixed” (shared by all individuals) in the population. Most mutations are lethal or have negative fitness consequences for the organism. Others have essentially no effect on organismal fitness and can become fixed through the neutral stochastic process known as random drift. However, mutations may also produce a selective advantage that boosts their chances of reaching fixation. Regions of genomes where new mutations are beneficial, rather than neutral or deleterious, tend to evolve more rapidly due to positive selection. Genes involved in immunity and defense are a well-known example; rapid evolution in these genes presumably occurs because new mutations help organisms to prevail in evolutionary “arms races” with pathogens. In recent years genome-wide scans for selection have enlarged our understanding of the genome evolution of various species. In this chapter, we will focus on methods to detect selection on the genome. In particular, we will discuss probabilistic models and how they have changed with the advent of new genome-wide data now available.Publisher PD

Reliability testing of urodynamics, pressure flow studies and cough leak point pressure in women with urodynamic stress incontinence with and without detrusor overactivity

Urodynamic studies which included cough leak point pressure (CLPP) and pressure flow studies were performed at two visits 2 weeks apart. Reproducibility between the two visits and also between the two diagnostic groups, urodynamic stress incontinence (USI) and urodynamic mixed incontinence (UMI) were analysed. Thirty-one women completed both visits, of those 14 had USI in both sets of urodynamic studies, 11 had UMI on both visits, six had USI on one visit and UMI in the other. The urodynamic variables of maximum cystometric capacity and CLPP have the most repeatability. Analysis in women with USI alone compared to USI with detrusor overactivity (DOA) showed that the repeatability for pressure flow parameters and CLPP was better in women without DOA, of which the CLPP was significantly different (p?=?0.036). Urodynamic variables are inconsistent. This may reflect variations in urinary tract behaviour

A critical review of diagnostic criteria for evaluating patients with symptomatic stress urinary incontinence.

Item does not contain fulltextThe first paper in this section is a review by several highly respected authors of diagnostic criteria for evaluating patients with symptomatic stress urinary incontinence, and is followed by a review of the role of urgency and its measurement in the overactive bladder symptom syndrome, with emphasis on current concepts and future prospects. These are two important papers, which point the reader in the direction of a greater understanding of these conditions. The concept of alpha-blockade before a trial without catheter after acute urinary retention is revisited by authors from the UK, who used tamsulosin in a randomized controlled trial. They found that it is appropriate to recommend tamsulosin for such use in this condition