scholarly journals In-Frame and Frameshift Mutations in Zebrafish presenilin 2 Affect Different Cellular Functions in Young Adult Brains

2021 ◽  
pp. 1-10
Author(s):  
Karissa Barthelson ◽  
Stephen Martin Pederson ◽  
Morgan Newman ◽  
Haowei Jiang ◽  
Michael Lardelli

Background: Mutations in PRESENILIN 2 (PSEN2) cause early onset familial Alzheimer’s disease (EOfAD) but their mode of action remains elusive. One consistent observation for all PRESENILIN gene mutations causing EOfAD is that a transcript is produced with a reading frame terminated by the normal stop codon—the “reading frame preservation rule”. Mutations that do not obey this rule do not cause the disease. The reasons for this are debated. Objective: To predict cellular functions affected by heterozygosity for a frameshift, or a reading frame-preserving mutation in zebrafish psen2 using bioinformatic techniques. Methods: A frameshift mutation (psen2N140fs) and a reading frame-preserving (in-frame) mutation (psen2T141 _ L142delinsMISLISV) were previously isolated during genome editing directed at the N140 codon of zebrafish psen2 (equivalent to N141 of human PSEN2). We mated a pair of fish heterozygous for each mutation to generate a family of siblings including wild type and heterozygous mutant genotypes. Transcriptomes from young adult (6 months) brains of these genotypes were analyzed. Results: The in-frame mutation uniquely caused subtle, but statistically significant, changes to expression of genes involved in oxidative phosphorylation, long-term potentiation and the cell cycle. The frameshift mutation uniquely affected genes involved in Notch and MAPK signaling, extracellular matrix receptor interactions and focal adhesion. Both mutations affected ribosomal protein gene expression but in opposite directions. Conclusion: A frameshift and an in-frame mutation at the same position in zebrafish psen2 cause discrete effects. Changes in oxidative phosphorylation, long-term potentiation and the cell cycle may promote EOfAD pathogenesis in humans.

2020 ◽  
Author(s):  
Karissa Barthelson ◽  
Stephen Martin Pederson ◽  
Morgan Newman ◽  
Haowei Jiang ◽  
Michael Lardelli

AbstractBackgroundMutations in PRESENILIN 2 (PSEN2) cause early disease onset familial Alzheimer’s disease (EOfAD) but their mode of action remains elusive. One consistent observation for all PRESENILIN gene mutations causing EOfAD is that a transcript is produced with a reading frame terminated by the normal stop codon – the “reading frame preservation rule”. Mutations that do not obey this rule do not cause the disease. The reasons for this are debated.MethodsA frameshift mutation (psen2N140fs) and a reading frame-preserving mutation (psen2T141_L142delinsMISLISV) were previously isolated during genome editing directed at the N140 codon of zebrafish psen2 (equivalent to N141 of human PSEN2). We mated a pair of fish heterozygous for each mutation to generate a family of siblings including wild type and heterozygous mutant genotypes. Transcriptomes from young adult (6 months) brains of these genotypes were analysed. Bioinformatics techniques were used to predict cellular functions affected by heterozygosity for each mutation.ResultsThe reading frame preserving mutation uniquely caused subtle, but statistically significant, changes to expression of genes involved in oxidative phosphorylation, long term potentiation and the cell cycle. The frameshift mutation uniquely affected genes involved in Notch and MAPK signalling, extracellular matrix receptor interactions and focal adhesion. Both mutations affected ribosomal protein gene expression but in opposite directions.ConclusionA frameshift and frame-preserving mutation at the same position in zebrafish psen2 cause discrete effects. Changes in oxidative phosphorylation, long term potentiation and the cell cycle may promote EOfAD pathogenesis in humans.


2013 ◽  
Vol 33 (2) ◽  
pp. 203-213 ◽  
Author(s):  
G Han ◽  
L An ◽  
B Yang ◽  
L Si ◽  
T Zhang

The aim of the present study was to investigate whether cognitive behavioral impairment, induced by nicotine in offspring rats, was associated with the alteration of hippocampal short-term potentiation (STP) and long-term potentiation (LTP) and to discuss the potential underlying mechanism. Young adult offspring rats were randomly divided into three groups. The groups include: control group (CC), nicotine group 1 (NC), in which their mothers received nicotine from gestational day 3 (GD3) to GD18, and nicotine group 2 (CN), in which young adult offspring rats received nicotine from postnatal day 42 (PD42) to PD56. Morris water maze (MWM) test was performed and then field excitatory postsynaptic potentials elicited by the stimulation of perforant pathway were recorded in the hippocampal dentate gyrus region. The results of the MWM test showed that learning and memory were impaired by either prenatal or postnatal nicotine exposure. In addition, it was found that there was no statistical difference of the MWM data between both nicotine treatments. In the electrophysiological test, LTP and STP were significantly inhibited in both NC and CN groups in comparison with the CC group. Notably, STP in CN group was also lower than that in the NC group. These findings suggested that both prenatal and postnatal exposure to nicotine induced learning and memory deficits, while the potential mechanism might be different from each other due to their dissimilar impairments of synaptic plasticity.


2011 ◽  
Vol 108 (13) ◽  
pp. 5437-5442 ◽  
Author(s):  
B. H. Singer ◽  
A. E. Gamelli ◽  
C. L. Fuller ◽  
S. J. Temme ◽  
J. M. Parent ◽  
...  

1998 ◽  
Vol 79 (4) ◽  
pp. 1790-1796 ◽  
Author(s):  
Gowri K. Pyapali ◽  
Dennis A. Turner ◽  
Christina L. Williams ◽  
Warren H. Meck ◽  
H. Scott Swartzwelder

Pyapali, Gowri K., Dennis A. Turner, Christina L. Williams, Warren H. Meck, and H. Scott Swartzwelder. Prenatal dietary choline supplementation decreases the threshold for induction of long-term potentiation in young adult rats. J. Neurophysiol. 79: 1790–1796, 1998. Choline supplementation during gestation in rats leads to augmentation of spatial memory in adulthood. We hypothesized that prenatal (E12–E17) choline supplementation in the rat would lead to an enhancement of hippocampal synaptic plasticity as assessed by long-term potentiation (LTP) at 3–4 mo of age. LTP was assessed blindly in area CA1 of hippocampal slices with first suprathreshold (above threshold for LTP generation in control slices) theta-burst stimulus trains. The magnitude of potentiation after these stimuli was not different between slices from control and prenatally choline supplemented animals. Next, threshold (reliably leading to LTP generation in control slices) or subthreshold theta-burst stimulus trains were applied to slices from control, prenatally choline-supplemented, and prenatally choline-deprived rats. Threshold level stimulus trains induced LTP in slices from both the control and choline-supplemented rats but not in those from the choline-deficient rats. Subthreshold stimulus trains led to LTP induction in slices from prenatally choline-supplemented rats only. These observations indicate that prenatal dietary manipulation of the amino acid, choline, leads to subsequent significant alterations of LTP induction threshold in adult animals.


2022 ◽  
Vol 15 ◽  
Author(s):  
Kimmo Lehtinen ◽  
Miriam S. Nokia ◽  
Heikki Takala

Optogenetics, a field concentrating on controlling cellular functions by means of light-activated proteins, has shown tremendous potential in neuroscience. It possesses superior spatiotemporal resolution compared to the surgical, electrical, and pharmacological methods traditionally used in studying brain function. A multitude of optogenetic tools for neuroscience have been created that, for example, enable the control of action potential generation via light-activated ion channels. Other optogenetic proteins have been used in the brain, for example, to control long-term potentiation or to ablate specific subtypes of neurons. In in vivo applications, however, the majority of optogenetic tools are operated with blue, green, or yellow light, which all have limited penetration in biological tissues compared to red light and especially infrared light. This difference is significant, especially considering the size of the rodent brain, a major research model in neuroscience. Our review will focus on the utilization of red light-operated optogenetic tools in neuroscience. We first outline the advantages of red light for in vivo studies. Then we provide a brief overview of the red light-activated optogenetic proteins and systems with a focus on new developments in the field. Finally, we will highlight different tools and applications, which further facilitate the use of red light optogenetics in neuroscience.


Sign in / Sign up

Export Citation Format

Share Document