What Does Microrna Clusters Means ? Same Promoters Or Different Promoters, But Closer Genomic Distances ?

Question

[jack]

Hi all,

In papers I've frequently face with miRNA clusters, but still it's not completely clear for me what they are. I have two different understanding from them, but I don't know which one is correct 1)They are in the same genomic region and transcripts together (they have same promoter) 2) They have different promoters but their genomics distance are less than sth like k bp? so they are not transcript together ?

[Ashutosh Pandey]

Can you give a few references ?

Answer 1

[Lorena Pantano]

miRBase defined as miRNAs that are closer than 1Kb. This is assumed because it is known that miRNA in the same genomic location, transcript together, from the same promoter, and then they are processed into the different miRNAs. But Not much experimental probes, so it is more a bioinformatic definitions, mainly. Dependending if the author's paper discovered the precursor transcript or not.