Question

The signaling role of small RNA molecules was not recognized for many years because:

A) Most animals lack miRNA
B) RNA can anneal to DNA
C) Small RNAs were considered to be mRNA degradation products
D) Techniques for RNA purification did not exist
E) Protein-RNA interactions are not common

Answer 1

The recognition of the signaling role of small RNAs was obscured because they were mistaken for mRNA degradation products, not understanding their true role in RNA interference and gene regulation.

Step-by-step explanation:

The signaling role of small RNA molecules was not initially recognized because small RNAs were considered to be mRNA degradation products. With advancements in molecular biology, it became apparent that these molecules, specifically micro RNAs (miRNAs) and small interfering RNAs (siRNAs), are involved in more complex biological processes such as RNA interference (RNAi). This natural regulatory mechanism is used by cells to protect against viral invasion and to regulate gene expression by base pairing with complementary mRNA molecules, leading to their degradation or blocking their translation into proteins.