3 publications mentioning cel-mir-50

Open access articles that are associated with the species Caenorhabditis elegans and mention the gene name mir-50. Click the [+] symbols to view sentences that include the gene name, or the word cloud on the right for a summary.

1

Although our searches of the PicTar, TargetScan and mirWIP target prediction databases provide no indication that C. elegans mir-50, -82 and -86 target their host gene (results not shown), the positional conservation of miRNA and protein coding genes described above suggests that, with the last shared common ancestor of C. elegans, H. contortus and Brugia being ~350 million years ago [56], there is selective pressure to maintain these genomic contexts.

Of the highly expressed miRNAs common to both parasites, five (lin-4, mir-45, mir-50, mir-71, mir-228) are shared with C. elegans, where all except mir-50 are also abundant (using the same read number criteria) [42].

Interestingly, we note that C. elegans mir-50 is also located intronically in the sense orientation within an essential gene, Y71G12B.

11a, and that the Brugia mir-50 host gene, Bm1_56215 (I/LWEQ domain containing protein, EDP28450), is a clear homologue of this gene.

11a, and both contain mir-190 homologues (both intronic, sense) which are > 70% identical to the nematode mir-50 mature sequences.

Moreover, an H. contortus mir-50 homologue was identified and, although classified as intergenic by the preliminary gene predictions used here, BLASTX analysis of ~4 kb of sequence surrounding hco-mir-50 against C. elegans proteins also provided a match to Y71G12B.

For example, the observation that mir-50 is located within a homologous gene in three different nematode species, argues strongly for the conservation of miRNA function and suggests a strong selective pressure to maintain this genomic positioning.

The intronic-sense context of Brugia mir-50 [46] was likewise confirmed.

Deeper conservation of this same miRNA/protein-coding gene organisation was also found: the D. melanogaster rhea gene (NCBI gene ID: 38978) and human talin 2 (NCBI gene ID: 83660) (which show 47% identity and 67% similarity to each other), both show 38% identity and 57% similarity at the amino acid level to the C. elegans mir-50 host gene Y71G12B.

2

Indeed, the introduction of a transgene carrying the mir-50 genomic locus failed to rescue the lethality associated with the mir-50 allele (unpublished data).

For example, the lethality linked to mir-50(n4099) (Table 2) might be a consequence of a loss-of-function of mir-50 or of an effect on the predicted host gene Y71G12B.

We were unable to generate homozygotes for alleles of mir-50 and mir-353.

mir-50 and mir-353 are in introns of genes that when inactivated by RNAi result in embryonic lethality and may explain why we could not isolate homozygotes for our new deletions.

3

A further seven of the L. sigmodontis miRNAs are identical to O. ochengi miRNAs found in the nodule fluid and three (miR-50-3p and Bantam-b,c) differ by 1 nt outside of the seed region (Figure  3).