Snapshot of DNA methylation changes associated with hybridization in Xenopus

2011 ◽  
Vol 43 (22) ◽  
pp. 1276-1280 ◽  
Author(s):  
Alie Patrick Koroma ◽  
Raymond Jones ◽  
Pawel Michalak

Hybridization often results in dramatic genome reconfigurations including epigenetic changes that control gene expression. Here we survey methylation patterns of interspecific Xenopus F1 hybrids relative to parental species X. laevis and X. muelleri, using methyl-sensitive amplification polymorphisms (MSAPs). Out of a total of 546 MSAP markers, 364 were effective in elucidating the difference in methylation patterns between the hybrids and the parental species. Principal coordinate analysis of methylated fragments revealed four distinct clusters with the two parental species separate from hybrid males and females. On average, hybrids were characterized by a higher proportion (70.6%) of methylated fragments compared with the parental species (64.5%), and this difference was consistent with previously observed disruptions of hybrid transcriptomes. The proportion of methylated fragments did not correlate with variation in genome size, as measured with flow cytometry. The levels of methylation in sterile hybrid males (73.8%) were higher than in fertile hybrid females (68.6%), but this difference was not statistically significant. A total of 76 methylated fragments (20.9%) were hybrid-unique, presumably originating from methylation alterations in hybrid genomes.

2020 ◽  
Author(s):  
Waldir M. Berbel-Filho ◽  
Andrey Tatarenkov ◽  
George Pacheco ◽  
Helder M. V. Espírito-Santo ◽  
Mateus G. Lira ◽  
...  

AbstractHybridisation is a major source of evolutionary innovation. However, several prezygotic and postzygotic factors influence its likelihood and evolutionary outcomes. Differences in mating systems can have a major effect on the extent and direction of hybridisation and introgression. In plants, epigenetic mechanisms help to stabilize hybrid genomes and contribute to reproductive isolation, but the relationship between genetic and epigenetic changes in animal hybrids is unclear. We analysed the extent of a unique case of natural hybridisation between two genetically distant mangrove killifish species with different mating systems, Kryptolebias hermaphroditus (self-fertilising) and K. ocellatus (outcrossing), and the methylation patterns of their hybrids. Hybridisation rate between the species ranged between 14% and 26%. Although co-existing parental species displayed highly distinct genetic (microsatellites and SNPs) and methylation patterns (37,000 differentially methylated cytosines), our results indicate that F1 hybrids are viable and able to backcross with parental species. Hybrids had predominantly intermediate methylation patterns (88.5% of the sites) suggesting additive effects, as expected from hybridisation between genetically distant species. Differentially methylated cytosines between hybrids and both parental species (5,800) suggest that introgressive hybridisation may play a role in generating novel genetic and epigenetic variation which could lead to species diversification. We also found a small percentage of non-additive epigenetic effects which might act as an evolutionary bet-hedging strategy and increase fitness under environmental change.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Weitao Chen ◽  
Ming Zou ◽  
Yuefei Li ◽  
Shuli Zhu ◽  
Xinhui Li ◽  
...  

AbstractGenome complexity such as heterozygosity may heavily influence its de novo assembly. Sequencing somatic cells of the F1 hybrids harboring two sets of genetic materials from both of the paternal and maternal species may avoid alleles discrimination during assembly. However, the feasibility of this strategy needs further assessments. We sequenced and assembled the genome of an F1 hybrid between Silurus asotus and S. meridionalis using the SequelII platform and Hi-C scaffolding technologies. More than 300 Gb raw data were generated, and the final assembly obtained 2344 scaffolds composed of 3017 contigs. The N50 length of scaffolds and contigs was 28.55 Mb and 7.49 Mb, respectively. Based on the mapping results of short reads generated for the paternal and maternal species, each of the 29 chromosomes originating from S. asotus and S. meridionalis was recognized. We recovered nearly 94% and 96% of the total length of S. asotus and S. meridionalis. BUSCO assessments and mapping analyses suggested that both genomes had high completeness and accuracy. Further analyses demonstrated the high collinearity between S. asotus, S. meridionalis, and the related Pelteobagrus fulvidraco. Comparison of the two genomes with that assembled only using the short reads from non-hybrid parental species detected a small portion of sequences that may be incorrectly assigned to the different species. We supposed that at least part of these situations may have resulted from mitotic recombination. The strategy of sequencing the F1 hybrid genome can recover the vast majority of the parental genomes and may improve the assembly of complex genomes.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1754-1754
Author(s):  
Giselle Greisman ◽  
June Kloubec ◽  
Alexandra Kazaks ◽  
Kelly Morrow ◽  
Cristen Harris

Abstract Objectives The nitrates found in beetroot juice (BR) are known to be a precursor of nitric oxide (NO). NO is a known vasodilator which allows more oxygen to travel in the blood and may improve muscle efficiency. This study aims to measure the effect of BR supplementation on performance on 500-meter row time for trained CrossFit athletes. Many past studies have analyzed the effect of BR on male athletes, this study aimed to include both males and females. Methods This study used a randomized, cross-over, double-blind, placebo-controlled design to measure 500-meter row time. Thirty athletes age 18–60 consumed either a 2.7 oz shot of BR (6.5 mmol nitrate) or a placebo nitrate-free beetroot juice (PL). Two hours later, they rowed 500 meters. After at least a seven-day washout period, athletes repeated the 500-meter row with either BR or PL for comparison. This study was performed from July 2019 – January 2020 and was conducted in Mercer Island, Washington. Results Ten males age 18.0 to 60.3 (median 47.7) and twenty females age 26.7 to 58.3 (median 43.8), participated in this study. Row times for the 500-meter row ranged from 88.2 seconds to 150.7 seconds. Data indicate that although 60% of all participants rowed faster with BR (mean 112.83 seconds), compared to PL (mean 113.40 seconds), the difference in the means of row times (−0.563) was not significant overall (P = 0.29). However, for the 10 males, row times were significantly faster (1.02 second difference, P = 0.04) on average with BR compared to PL. For the 20 females, the difference in mean row time (−0.335 seconds) was not significant (P = 0.66). Competitive rowers were defined as those who rowed under 110 seconds (N = 15). For competitive rowers (10 males, 5 females), row times were significantly faster with BR compared to PL (difference in means −0.94, P = 0.009). However, for those rowers, the P-value of drink * group was 0.015. Conclusions Dietary nitrate improved indoor rowing performance in males but not in females. In addition, competitive rowers were also significantly faster with BR, however, there may be an order bias, since there was significant interaction between beverage type and testing order. Food based nitrate supplements may increase rowing performance with male rowers. Funding Sources Supported by Bastyr Faculty Student Research Grant.


Author(s):  
C. Boulard ◽  
J. Thévenin ◽  
O. Tranquet ◽  
V. Laporte ◽  
L. Lepiniec ◽  
...  

1974 ◽  
Vol 71 (12) ◽  
pp. 5057-5061 ◽  
Author(s):  
T. Barrett ◽  
D. Maryanka ◽  
P. H. Hamlyn ◽  
H. J. Gould

1984 ◽  
Vol 44 (2) ◽  
pp. 219-224 ◽  
Author(s):  
Ursula Mittwoch ◽  
Shantha Mahadevaiah ◽  
Leslie A. Setterfield

SUMMARYTwo male-sterile chromosome anomalies, the insertion Is(7; 1)40H and the tertiary trisomy, Ts(512)31H, were found to be associated with reduced ovarian volumes in immature females. Together with the reciprocal translocation, T(11; 19)42H, in which this effect was described previously, reduced ovaries have been found in all three male-sterile chromosome anomalies investigated so far, suggesting that ovarian involvement is likely to be common in these conditions. Assuming that the smaller ovarian size reflects a reduction in the number of oocytes, it is suggested that male-sterile chromosome anomalies may exert basically similar deleterious effects on meiotic germ cells in males and females, the difference in outcome being due to cell-physiological differences between spermatocytes and oocytes and to the small number of surviving oocytes required for fertility in females.


2021 ◽  
Vol 120 (3) ◽  
pp. 354a
Author(s):  
Anand P. Singh ◽  
Ping Wu ◽  
Eric F. Wieschaus ◽  
Jared E. Toettcher ◽  
Thomas Gregor

Genetics ◽  
1994 ◽  
Vol 138 (4) ◽  
pp. 1163-1170 ◽  
Author(s):  
E Wojcik ◽  
A M Murphy ◽  
H Fares ◽  
K Dang-Vu ◽  
S I Tsubota

Abstract A hybrid dysgenesis-induced mutation, enhancer of rudimentaryp1 (e(r)p1), is a recessive enhancer of a weak rudimentary mutant phenotype in Drosophila melanogaster. The e(r) gene was cloned using P element tagging and localized to region 8B on the X chromosome. It encodes a 1.0-kb and a 1.2-kb transcript. The 1.0-kb transcript is present in both adult males and females, while the 1.2-kb transcript is predominantly found in females. The difference in the lengths of the two e(r) transcripts is caused by two different polyadenylation sites spaced 228 bp apart. The amounts of both of these transcripts are drastically reduced in the e(r)p1 mutant. The P element in e(r)p1 is inserted in the 5'-untranslated leader region near the start of transcription. It may be producing its effect by suppressing transcription and/or by providing transcription termination and polyadenylation signals. The putative e(r) protein is 104 amino acids in length and bears no striking resemblance to protein sequences in GenBank or PIR. While its biochemical function is unknown at this time, sequence analysis indicates that the e(r) protein is highly conserved and, presumably, functionally very important. The amino acid sequences of the D. melanogaster and the Drosophila virilis proteins are 95% identical.


2018 ◽  
Vol 11 (10) ◽  
pp. 30
Author(s):  
Boushra Abdul-Aziz AlGhamdi ◽  
Shorouq Ali AL-Garni ◽  
Maysa M. Qutob

This study compares males and females perception of the effect of social media on their social interaction to understand the difference between both genders. The study follows a mixed-method methodology using a questionnaire with closed-ended items and open-ended questions. Responses to the questionnaire are collected form 207 male and female students from a public university in Saudi Arabia. In general, the results of the questionnaire are insignificant which indicate that there are no differences between both genders. However, the results of the open-ended questions show that females have a negative view of the effect of social media on human relations while males have a positive point of view. However, both genders have a positive point of view regarding balancing between friends and family in real life and virtual world through time management.


2016 ◽  
Vol 17 (5) ◽  
pp. 382-387 ◽  
Author(s):  
Kamalakanth Shenoy ◽  
George Attokaran

ABSTRACT Background Selecting and replacing missing teeth to natural proportions and esthetic preference of a patient in the absence of pre-extraction records is a very challenging task. Although facial analysis and proportions are well discussed in many populations, none exists for the Thrissur, Kerala, population. A prosthodontic rehabilitation for Kerala patients relying on other racial norms may result in dissonant facial proportions. Therefore, the purpose of this study was (1) to evaluate the validity of innercanthal distance as a guide in determining the mesiodistal dimension of six maxillary anterior teeth in a selected Malayalee population in the Thrissur Municipal Corporation area; (2) to check whether innercanthal distance undergoes dynamic changes over time as a result of aging; and (3) to evaluate whether there is a gender difference in the analyzed mean facial and dental proportions in this population. Materials and methods The study was conducted on 1,200 subjects in the Thrissur Municipal Corporation area. From five wards, 240 subjects were selected, out of which 120 were from the 18 to 25 years age group and 120 from the 40 to 50 years age group. Sixty males and females were selected from each group. The innercanthal distance was measured using a Digital Vernier Caliper, and alginate impressions were made to evaluate the size of maxillary anteriors. The data was analyzed statistically. Results The study showed that there is a high statistical significance between the innercanthal distance and the mesiodistal width of six maxillary anterior teeth in females (p < 0.01) and no significance in males. There was also dynamic changes in the innercanthal dimension and the mesiodistal width of maxillary anteriors with increase in age (p < 0.001). The difference in the mean of innercanthal distance between the genders was highly statistically significant, but no significance was found between the genders in the mesiodistal width of maxillary anteriors. Conclusion Within the population evaluated, there was a high statistical significance in females between the innercanthal distance and the mesiodistal width of six maxillary anterior teeth, but not for males. Innercanthal dimension was found to undergo dynamic changes as age increases in both males and females, and it was much higher in males than in females. There was no statistical significance in the comparative evaluation of mesiodistal width of maxillary anteriors of males and females in the study. Clinical significance Teeth selection is a critical step in determining the outcome of successful prosthodontic treatment. No definite guidelines for the selection of maxillary anterior teeth pertaining to the Thrissur, Kerala, population exist. A prosthodontic rehabilitation of Thrissur, Kerala, patients relying on other racial norms will result in dissonant facial proportions. In selecting maxillary anterior teeth, the knowledge of racial norms will help specify certain esthetic and functional modifications in treatment plans, which might be specific to each group. Therefore, there remains an unquestionable need for a scientific and reliable method for maxillary anterior teeth selection, which can be applied on this group of Indian population. How to cite this article Attokaran G, Shenoy K. Correlation between Innercanthal Distance and Mesiodistal Width of Maxillary Anterior Teeth in a Thrissur, Kerala, India, Population. J Contemp Dent Pract 2016;17(5):382-387.


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