Enhanced silk yield in transgenic silkworm ( Bombyx mori ) via ectopic expression of BmGT1‐L in the posterior silk gland

2020 ◽  
Author(s):  
X. Tang ◽  
H. Liu ◽  
Z. Shi ◽  
Q. Chen ◽  
X. Kang ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Ectopic Expression ◽  
Silk Gland ◽  
Transgenic Silkworm ◽  
Silkworm Bombyx Mori ◽  
Posterior Silk Gland

scholarly journals EXTRUSION OF NUCLEAR MATERIALS INTO CYTOPLASM IN THE POSTERIOR SILK GLAND CELLS OF SILKWORM, BOMBYX MORI

1968 ◽  
Vol 36 (3) ◽  
pp. C5-10 ◽  
Author(s):  
Yutaka Tashiro ◽  
Shiro Matsuura ◽  
Takashi Morimoto ◽  
Sunao Nagata
Keyword(s):  
Bombyx Mori ◽  
Silk Gland ◽  
Nuclear Materials ◽  
Gland Cells ◽  
Silkworm Bombyx Mori ◽  
Posterior Silk Gland

scholarly journals STUDIES ON THE POSTERIOR SILK GLAND OF THE SILKWORM, BOMBYX MORI

1968 ◽  
Vol 38 (3) ◽  
pp. 574-588 ◽  
Author(s):  
Yutaka Tashiro ◽  
Takashi Morimoto ◽  
Shiro Matsuura ◽  
Sunao Nagata
Keyword(s):  
Bombyx Mori ◽  
Early Stage ◽  
Larval Instar ◽  
Silk Gland ◽  
Exponential Increase ◽  
Wet Weight ◽  
Rough Er ◽  
Electron Microscopical ◽  
Silkworm Bombyx Mori ◽  
Posterior Silk Gland

Growth of the posterior silk gland and biosynthesis of fibroin during the fifth larval instar of the silkworm, Bombyx mori, have been studied. In accordance with the exponential increase in the wet weight of the gland, the amounts of DNA, RNA, protein, and lipids per animal increased rapidly in the early stage of the fifth instar (0–96 hr). Biosynthesis of fibroin, on the contrary, mainly proceeds in the later stage of the fifth instar (120–192 hr). Electron microscopical observations have shown that, in the very early stage (0–12 hr), a number of free ribosomes exist in the cytoplasm. Rough endoplasmic reticulum (ER) with closely spaced cisternae was also observed. Then rough ER starts to proliferate rapidly, and at the same time lamellar ER is rapidly or gradually transformed into vesicular or tubular forms. In the later stage of the fifth instar (120–192 hr), the cytoplasm is mostly filled with tubular or vesicular ER. Golgi vacuoles, free vacuoles (fibroin globules), and mitochondria are also observed. It is concluded that in the early stage of the fifth instar the cellular structures necessary for the biosynthesis of fibroin are rapidly formed, while in the later stage the biosynthesis of fibroin proceeds at a maximum rate and utilizes these structures.

scholarly journals Studies on the posterior silk gland of the silkworm Bombyx mori. V. Electron microscope localization of fibroin in the posterior silk gland at the later stage of the fifth instar.

1976 ◽  
Vol 70 (3) ◽  
pp. 648-659 ◽  
Author(s):  
S Sasaki ◽  
Y Tashiro
Keyword(s):  
Electron Microscope ◽  
Epoxy Resin ◽  
Bombyx Mori ◽  
Secretory Granules ◽  
Silk Gland ◽  
Fibrous Materials ◽  
Thin Sections ◽  
Dense Granules ◽  
Silkworm Bombyx Mori ◽  
Posterior Silk Gland

Electron microscope observations of thin sections of epoxy resin-embeded posterior silk gland cells at the later stage of the fifth instar revealed that the Golgi vacuoles and the secretory granules (fibroin globules) in the cytoplasm and the glandular lumen contain fine fibrous materials. In frozen thin sections these structures appear as electron-dense granules and electron-dense blocks, or a column, respectively. Immunoelectron microscopy has shown that ferritin particles or products of the peroxidase reaction are localized on these structures. It was concluded that the fine fibrous materials most probably represent native fibroin molecules or their aggregates.

The mechanism of damage to the posterior silk gland by trace amounts of acetamiprid in the silkworm, Bombyx mori

2020 ◽  
Vol 170 ◽  
pp. 104676
Author(s):  
Zhengting Lu ◽  
Mengxue Li ◽  
Yilong Fang ◽  
Jianwei Qu ◽  
Wentao Ye ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Silk Gland ◽  
Silkworm Bombyx Mori ◽  
Posterior Silk Gland

scholarly journals STUDIES ON THE POSTERIOR SILK GLAND OF THE SILKWORM, BOMBYX MORI

1968 ◽  
Vol 38 (3) ◽  
pp. 589-603 ◽  
Author(s):  
Shiro Matsuura ◽  
Takashi Morimoto ◽  
Sunao Nagata ◽  
Yutaka Tashiro
Keyword(s):  
Bombyx Mori ◽  
Silk Gland ◽  
Ultrastructural Changes ◽  
Prepupal Stage ◽  
Smooth Membrane ◽  
Wet Weight ◽  
Rough Er ◽  
Silkworm Bombyx Mori ◽  
Myelin Figures ◽  
Posterior Silk Gland

Cytolytic processes in posterior silk gland cells of the silkworm, Bombyx mori, during metamorphosis from larva to pupa have been studied. During this stage, the wet weight and the amounts of RNA and protein of the gland decrease rapidly and markedly, while the amount of DNA decreases slowly and slightly. The ultrastructural changes observed at the beginning of the prepupal stage consist of the appearance or the increase in the number of autophagosomes containing endoplasmic reticulum (ER), or "early autophagosomes" as we have called them, which seem to be gradually transformed to autolysosomes. A number of usual lysosomes, which frequently contain myelin figures, also appear in the cytoplasm. Sometimes they fuse with each other to form large conglomerates. In the middle of the prepupal stage, a number of smooth membrane-bounded vacuoles appear in cytoplasm. Towards the end of the prepupal stage the partition or sequestration of cytoplasm was observed. Thus large autophagosomes containing cytoplasmic organelles such as rough ER and/or mitochondria are formed. The nucleus is partitioned in a similar way by smooth membranes, and then autophagosomes containing condensed chromatin blocks are formed. These various kinds of autophagosomes, or "late autophagosomes" as we have generally called them, are continuously released into the hemolymph until the gland is completely disintegrated.

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