Mutation of a Cuticular Protein,BmorCPR2, Alters Larval Body Shape and Adaptability in Silkworm,Bombyx mori

SummarySeveral genetic mosaics for larval body marking of the silkworm, Bombyx mori, have been induced by X-ray irradiation. It is hypothesized that the occasional loss of chromosomal fragments carrying the genes for body marking during development may give rise to this type of mosaicism. Using pulsed field gel electrophoresis (PFGE), we find that a DNA molecule of about 2·5 megabases (Mb) is present in one type of mosaic (mottled striped strains pSm788 and pSm872), and not in any other strain. This DNA fragment hybridizes strongly with some chorion genes which are less than 6·9 cM away from the ps locus, and hence it corresponds to a chromosomal fragment containing genes for both striped marking (ps) and the chorion. In the non-mottled ps strain, the phenotype before X-ray irradiation, no band was detected either on a PFGE gel or after hybridization with the chorion probe. These results suggest that the mottled ps strains carry short chromosome fragments which are lost differentially during cell divisions.

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Identification and molecular characterization of a sex chromosome rearrangement causing a soft and pliable (spli) larval body phenotype in the silkworm, Bombyx mori

Genome ◽

10.1139/g09-083 ◽

2010 ◽

Vol 53 (1) ◽

pp. 45-54 ◽

Cited By ~ 3

Author(s):

Tsuguru Fujii ◽

Seigo Kuwazaki ◽

Kimiko Yamamoto ◽

Hiroaki Abe ◽

Akio Ohnuma ◽

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Keyword(s):

Bombyx Mori ◽

Sex Chromosome ◽

Chromosome Rearrangement ◽

Artificial Chromosome ◽

Chromosome Breakage ◽

Z Chromosome ◽

Larval Body ◽

Cytogenetic Analyses ◽

Eye Pigmentation ◽

Silkworm Bombyx Mori

We carried out genetic and cytogenetic analyses of X-ray-induced deleterious Z chromosomes that result in a soft and pliable (spli) phenotype in the silkworm, Bombyx mori . In a B. mori strain with a spli phenotype, we found the Z chromosome broken between the sch (1–21.5) and od (1–49.6) loci. We also found a chromosomal fragment bearing a fifth-chromosome locus for egg and eye pigmentation fused to a Z chromosome fragment. By means of fluorescence in situ hybridization using bacterial artificial chromosome clones as probes, we confirmed that the fused chromosome is composed of a fragment of chromosome 5 and a fragment of the Z chromosome. Moreover, a predicted gene, GA002017, the Bombyx ortholog of the Drosophila gene acj6 (Bmacj6), was completely deleted by the Z chromosome breakage event. The relationship between Bmacj6 and the spli phenotype is discussed.

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A corset function of exoskeletal ECM promotes body elongation in Drosophila

Communications Biology ◽

10.1038/s42003-020-01630-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Reiko Tajiri ◽

Haruhiko Fujiwara ◽

Tetsuya Kojima

Keyword(s):

Mechanical Property ◽

General Feature ◽

Body Shape ◽

The Body ◽

Cuticular Protein ◽

Larval Body ◽

Larval Cuticle ◽

Round Shape ◽

Extracellular Materials ◽

Protein Components

AbstractBody elongation is a general feature of development. Postembryonically, the body needs to be framed and protected by extracellular materials, such as the skeleton, the skin and the shell, which have greater strength than cells. Thus, body elongation after embryogenesis must be reconciled with those rigid extracellular materials. Here we show that the exoskeleton (cuticle) coating the Drosophila larval body has a mechanical property to expand less efficiently along the body circumference than along the anteroposterior axis. This “corset” property of the cuticle directs a change in body shape during body growth from a relatively round shape to an elongated one. Furthermore, the corset property depends on the functions of Cuticular protein 11 A and Tubby, protein components of a sub-surface layer of the larval cuticle. Thus, constructing a stretchable cuticle and supplying it with components that confer circumferential stiffness is the fly’s strategy for executing postembryonic body elongation.

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The silkworm Bombyx mori cuticular protein CPR55 gene is regulated by the transcription factor βFTZ-F1

The Journal of Basic & Applied Zoology ◽

10.1016/j.jobaz.2015.06.001 ◽

2016 ◽

Vol 73 ◽

pp. 20-27 ◽

Cited By ~ 1

Author(s):

Md. Saheb Ali ◽

Birendra Mishra ◽

R.F. Rahman ◽

Ahsanul Haque Swapon

Keyword(s):

Transcription Factor ◽

Bombyx Mori ◽

Cuticular Protein ◽

Silkworm Bombyx Mori

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Effect of SSP – 11 on Weight and Tissue Composition of 4th Instar Larvae of Silkworm, Bombyx mori

ENTOMOLOGIA HELLENICA ◽

10.12681/eh.14006 ◽

2017 ◽

Vol 11 ◽

pp. 11

Author(s):

K. Υenkata Rami Reddy ◽

K. Sashindran Nair ◽

S. Β. Magadum ◽

R. Κ. Datta

Keyword(s):

Bombyx Mori ◽

Artificial Diet ◽

Fat Body ◽

Activity Levels ◽

Tissue Composition ◽

Fresh Weight ◽

Total Proteins ◽

Larval Body ◽

Total Carbohydrates ◽

Silkworm Bombyx Mori

The anti-juvenoid, SSP-11 ((E) 4-chloro-a, a, a-trifluro-N [ 1 (1 H-imidazole- 1 –y1)- 2-propoxy ethylyledene] O, toludine) was used to induce trimoulters from tetramoulter larvae of the silkworm, Bombyx mori (race NB7). The compound was fed for two days through an artificial diet at the concentration of 200 ppm to newly ecdysed 4th stadium larvae. Body and silkgland fresh weight were recorded daily in the 4th larval stadium and protein profiles of haemolymph, fat body and silkgland were determined at the end of the stadium. In larvae treated with SSP-11, feeding period in stadium 4 was prolonged by 3-4 days and 80-85% of the larvae started to spin as trimoulters. Eight and thirty fold increases in the larval body and silkgland weights respectively were the result of SSP-11. Further, total proteins, total carbohydrates, glycogen and nucleic acid (DNA & RNA) also increased. The activity levels of alanine aminotransferase and aspartate aminotransferasc increased significantly than in the control indicating increased mobilization of aminoacids into transamination activities.

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