Let-7 microRNA is a critical regulator in controlling the growth and function of silk gland in the silkworm.

ABSTRACT: The silk gland is characterized by high protein synthesis. However, the molecular mechanisms controlling silk gland growth and silk protein synthesis remain undetermined. Here we demonstrated that CRISPR/Cas9-based knockdown of let-7 or the whole cluster promoted endoreduplication and enlargement of the silk gland, accompanied by changing silk yield, whereas transgenic overexpression of let-7 led to atrophy and degeneration of the silk gland. Mechanistically, let-7 controls cell growth in the silk gland through coordinating nutrient metabolism processes and energy signalling pathways. Transgenic overexpression of pyruvate carboxylase, a novel target of let-7, resulted in enlargement of the silk glands, which is consistent with the abnormal phenotype of the let-7 knockdown. Overall,

SUBMITTER: Wang W 

PROVIDER: S-EPMC7237193 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature