Search results for "MyoD"

Selection on two behavioral genes : fitness effects of receptor genes for arginine vasopressin 1a and oxytocin in the bank vole Myodes glareolus

2017

Most variation in behavior is regulated by genes; nevertheless the mechanisms behind maintenance of genetic diversity at behavioral loci have remained mainly elusive in natural populations. I studied in my thesis selection mechanisms of two genes associated with socio-sexual behavior, arginine vasopressin receptor 1a (Avpr1) and oxytocin receptor (Oxtr) in bank vole (Myodes glareolus). Expression of Avpr1a and Oxtr in specific regions of the brain regulates diverse social and reproductive behaviors such as parental care, aggression, sexual behavior, social recognition as well as pair and parent- offspring bonding in mammals. In addition, there is a link between the length of a regulatory re…

Maintenance of genetic diversity in cyclic populations—a longitudinal analysis in Myodes glareolus

2012

Conspicuous cyclic changes in population density characterize many populations of small northern rodents. The extreme crashes in individual number are expected to reduce the amount of genetic variation within a population during the crash phases of the population cycle. By long-term monitoring of a bank vole (Myodes glareolus) population, we show that despite the substantial and repetitive crashes in the population size, high heterozygosity is maintained throughout the population cycle. The striking population density fluctuation in fact only slightly reduced the allelic richness of the population during the crash phases. Effective population sizes of vole populations remained also relative…

Conservation implications of change in antipredator behavior in fragmented habitat: Boreal rodent, the bank vole, as an experimental model

2015

Abstract Habitat fragmentation is known to cause population declines but the mechanisms leading to the decline are not fully understood. Fragmentation is likely to lead to changes in predation risk, which may cause behavioral responses with possible population level consequences. It has recently been shown that the awareness of predator presence, resulting in a fear response, strongly affects behavior and physiology of the prey individuals. Costs arising from fear may be as important for the prey population size as the direct killing of prey. We tested how predation risk in the form of scent of a specialist predator, the least weasel (Mustela nivalis nivalis), affects bank vole (Myodes glar…

Variable mode of estrus affects female decision for multiple mating

2011

Investigating patterns of variation in mating strategies may shed light on their evolutionary importance as well as their impact on the strength and shape of sexual selection. Multimale mating (polyandry) and mate choice are intensely studied subjects in the area of sexual selection, but little is known about intraspecific patterns of variation that may respond to dynamic cost-benefit balances. In a laboratory study, we investigated the mating behavior of female bank voles (Myodes glareolus) with distinctly different time and energy budgets: They were either in cycling estrus (CE) or postpartum estrus (PPE) shortly after delivery. Postpartum mating is highly constrained by time and energy d…

Is Mating Alone Enough to Inhibit Infanticide in Male Bank Voles?

2010

Infanticide, the killing of conspecific young, is commonly recognized as an adaptive behavioural strategy enhancing the fitness of the perpetrator. Infanticide is supposed to be inhibited in several male rodent species after mating with a time lag to the time when perpetrators own offspring would be born. This is because males with no parental care do not recognize their own offspring. It has been suggested that copulation alone is enough to inhibit infanticidal behaviour in male rodents. Infanticidal behaviour occurs in more than 50% of male bank voles (Myodes glareolus), and offspring loss because of infanticide may have a great effect on breeding success and population recruitment. In a …

Epigenetic mechanisms behind phenotypic changes in different population densities in bank voles (Myodes glareolus)

2017

Metsämyyrän (Myodes glareolus) fenotyyppisten muutosten epigeneettiset mekanismit eri populaatiotiheyksissä. Epigeneettisilla mekanismeilla on perustava rooli normaalissa geeniekspression aktiivisuudessa ja ne voidaan nähdä molekulaaristen prosessien systeeminä, joka reagoi ympäristötekijöihin ja säätelee geenisäätelyä muuttamatta alkuperäistä DNA-sekvenssiä. DNA-metylaatio on eniten tutkittu epigeneettinen mekanismi jolla on tärkeä rooli geenien säätelyssä normaalin solujen kehityksen aikana. Metylaatio ilmenee tyypillisesti CpG-dinukleotideissa, joissa metyyliryhmä kiinnittyy 5’-sytosiiniin (C) jota seuraava emäs on guaniini (G). Tämä voi estää näihin CpG-paikkoihin liittyvien geenien ilm…

Chronic Background Radiation Correlates With Sperm Swimming Endurance in Bank Voles From Chernobyl

2022

Sperm quantity and quality are key features explaining intra- and interspecific variation in male reproductive success. Spermatogenesis is sensitive to ionizing radiation and laboratory studies investigating acute effects of ionizing radiation have indeed found negative effects of radiation on sperm quantity and quality. In nature, levels of natural background radiation vary dramatically, and chronic effects of low-level background radiation exposure on spermatogenesis are poorly understood. The Chernobyl region offers a unique research opportunity for investigating effects of chronic low-level ionizing radiation on reproductive properties of wild organisms. We captured male bank voles (Myo…

Experimental investigation of a hantavirus host-switch between arvicoline rodents Lemmus lemmus and Myodes glareolus

2014

The effects of Borrelia infection on its wintering rodent host

2022

AbstractIn seasonal environments, appropriate adaptations are crucial for organisms to maximize their fitness. For instance, in many species, the immune function has been noticed to decrease during winter, which is assumed to be an adaptation to the season’s limited food availability. Consequences of an infection on the health and survival of the host organism could thus be more severe in winter than in summer. Here, we experimentally investigated the effect of a zoonotic, endemic pathogen, Borrelia afzelii infection on the survival and body condition in its host, the bank vole (Myodes glareolus), during late autumn–early winter under semi-natural field conditions in 11 large outdoor enclos…

Exposure to environmental radionuclides alters mitochondrial DNA maintenance in a wild rodent

2020

AbstractMitochondria are sensitive to oxidative stress, including that derived from ionizing radiation. To quantify the effects of exposure to environmental radionuclides on mitochondrial DNA (mtDNA) dynamics in wildlife, bank voles (Myodes glareolus) were collected from the chernobyl exclusion zone (CEZ), where animals are exposed to elevated levels of radionuclides, and from uncontaminated areas within the CEZ and elsewhere in Ukraine. Brains of bank voles from outside the CEZ were characterized by low mtDNA copy number and low mtDNA damage; by contrast, bank voles within the CEZ had high mtDNA copy number and high mtDNA damage, consistent with putative damaging effects of elevated radiat…