A mutation in the Bombyx mori BmSPI51 gene results in alterations protein abundance in cocoon and unveils compensatory mechanism of silk gland proteinase inhibitors.

Proteinase inhibitors constitute a significant component of Lepidoptera cocoon. BmSPI51 is the most abundant protease inhibitors in silkworm cocoons. In this study, we aimed to elucidate the biological function of BmSPI51 in both the silkworm silk gland and cocoon formation.

Mutation in the Bombyx mori BmGMC2 gene impacts silk production and silk protein synthesis.

Silk is a natural protein fiber that is predominantly comprised of fibroin and sericin. In addition, it contains seroins, protease inhibitors, enzymes, and other proteins. We found an ecdysone oxidase BmGMC2, notably, which is specifically and highly expressed only in the silk glands of silkworms (Bombyx mori L.

MicroRNA let-7 targets BmCDK1 to regulate cell proliferation and endomitosis of silk gland in the silkworm, Bombyx mori.

MicroRNAs play critical roles in multiple developmental processes in insects. Our previous study showed that CRISPR/Cas9-mediated knock down of the microRNA let-7 in silkworms increased the size of larvae and silk glands, thereby improving the silk production capacity. In this study, we elucidate the molecular mechanism underlying of let-7 regulates growth.

Identification and functional study of fhx-L1, a major silk component in Bombyx mori.

The silkworm cocoon was composed of fibroins, sericins, protease inhibitors, and proteins of unknown function. In this study, we focused on fhx-L1 (fibrohexamerin-like1), which was the homolog of fibroin fhx (fibrohexamerin). We identified 154 fhx family genes in 44 Lepidoptera insects, and seven fhx-Ls were found in Bombyx mori.

A novel method for silkworm cocoons self-degumming and its effect on silk fibers.

Introduction: Conventional hot-alkaline cocoon degumming techniques greatly weaken the physicochemical and mechanical properties of silk fibroin fiber, thus affecting the quality of silk fabric. Moreover, it causes massive energy waste and serious environmental pollution.

Objective: This study aims to establish a novel cocoon self-degumming method by genetic modification of silkworm varieties and silk fibers.