Limits...
Selection Against Maternal microRNA Target Sites in Maternal Transcripts.

Marco A - G3 (Bethesda) (2015)

Bottom Line: In Drosophila melanogaster, a large number of maternal products are found in the oocyte, some of which are indispensable.A potential role of the maternal microRNA mir-9c in maternal-to-zygotic transition is also discussed.In conclusion, maternal microRNAs in Drosophila have a functional impact in maternal protein-coding transcripts.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom amarco.bio@gmail.com.

No MeSH data available.


Maternal microRNA target avoidance. (A) Target avoidance (see Results) for microRNAs with differences abundances in the unfertilized egg (NULL, not detected; LOW, less than 0.1% of the set; MID, between 0.1 and 1%, HIGH, more than 1%). Error bars represent the SEM. Asterisks show statistically significant differences (p < 0.01) for t-test with unequal variances. (B) Target conservation for microRNAs with differences abundances in the unfertilized egg. (C) Distribution shifting to the left of allele frequency distribution in maternal transcripts with respect to zygotic transcripts.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4593001&req=5

fig5: Maternal microRNA target avoidance. (A) Target avoidance (see Results) for microRNAs with differences abundances in the unfertilized egg (NULL, not detected; LOW, less than 0.1% of the set; MID, between 0.1 and 1%, HIGH, more than 1%). Error bars represent the SEM. Asterisks show statistically significant differences (p < 0.01) for t-test with unequal variances. (B) Target conservation for microRNAs with differences abundances in the unfertilized egg. (C) Distribution shifting to the left of allele frequency distribution in maternal transcripts with respect to zygotic transcripts.

Mentions: To explore whether this pattern is a general feature of maternal microRNAs I defined “target avoidance” as the log2 ratio of the number of target sites with an allele frequency smaller than 0.1 (that is, the frequency of sites where >90% of alleles are the nontarget sequence) between maternal and zygotic transcripts. In this context, positive values indicate that targets for a specific microRNA tend to be “avoided” by maternal transcripts, that is, there is selection against target sites for maternal microRNAs in maternal transcripts. Figure 5A is a bar plot of target avoidance values for different levels of microRNA abundance in the egg. Maternally deposited coding transcripts tend to avoid some target sites for highly abundant maternal microRNAs (with respect to zygotic transcripts). Differences were statistically significant (Figure 5A). In a similar manner, I defined “target conservation” as the log2 ratio of the number of target sites with allele frequency greater than 0.9 between maternal and zygotic transcripts. A positive value indicates that target-sites are preferentially conserved in maternal transcripts. Figure 5B shows these values for different microRNA abundances. Overall, maternal transcripts conserve some target sites, but there is not a distinctive profile between maternal and nonmaternal microRNAs (Figure 5B).


Selection Against Maternal microRNA Target Sites in Maternal Transcripts.

Marco A - G3 (Bethesda) (2015)

Maternal microRNA target avoidance. (A) Target avoidance (see Results) for microRNAs with differences abundances in the unfertilized egg (NULL, not detected; LOW, less than 0.1% of the set; MID, between 0.1 and 1%, HIGH, more than 1%). Error bars represent the SEM. Asterisks show statistically significant differences (p < 0.01) for t-test with unequal variances. (B) Target conservation for microRNAs with differences abundances in the unfertilized egg. (C) Distribution shifting to the left of allele frequency distribution in maternal transcripts with respect to zygotic transcripts.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4593001&req=5

fig5: Maternal microRNA target avoidance. (A) Target avoidance (see Results) for microRNAs with differences abundances in the unfertilized egg (NULL, not detected; LOW, less than 0.1% of the set; MID, between 0.1 and 1%, HIGH, more than 1%). Error bars represent the SEM. Asterisks show statistically significant differences (p < 0.01) for t-test with unequal variances. (B) Target conservation for microRNAs with differences abundances in the unfertilized egg. (C) Distribution shifting to the left of allele frequency distribution in maternal transcripts with respect to zygotic transcripts.
Mentions: To explore whether this pattern is a general feature of maternal microRNAs I defined “target avoidance” as the log2 ratio of the number of target sites with an allele frequency smaller than 0.1 (that is, the frequency of sites where >90% of alleles are the nontarget sequence) between maternal and zygotic transcripts. In this context, positive values indicate that targets for a specific microRNA tend to be “avoided” by maternal transcripts, that is, there is selection against target sites for maternal microRNAs in maternal transcripts. Figure 5A is a bar plot of target avoidance values for different levels of microRNA abundance in the egg. Maternally deposited coding transcripts tend to avoid some target sites for highly abundant maternal microRNAs (with respect to zygotic transcripts). Differences were statistically significant (Figure 5A). In a similar manner, I defined “target conservation” as the log2 ratio of the number of target sites with allele frequency greater than 0.9 between maternal and zygotic transcripts. A positive value indicates that target-sites are preferentially conserved in maternal transcripts. Figure 5B shows these values for different microRNA abundances. Overall, maternal transcripts conserve some target sites, but there is not a distinctive profile between maternal and nonmaternal microRNAs (Figure 5B).

Bottom Line: In Drosophila melanogaster, a large number of maternal products are found in the oocyte, some of which are indispensable.A potential role of the maternal microRNA mir-9c in maternal-to-zygotic transition is also discussed.In conclusion, maternal microRNAs in Drosophila have a functional impact in maternal protein-coding transcripts.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom amarco.bio@gmail.com.

No MeSH data available.