Biochemical studies on the formation of the silkprotein

(XII) The functional localization of the silkgland on the amino acid absorption

Abstract

1) The current experiment was carried out, in relation to silkprotein biosynthesis, to clarify the functional localization of the silkgland on the amino acid absorption.
2) A pair of silkglands was isolated from the silkworm one hour after 0.5μc per head of the C¹⁴ amino acids, such as C¹⁴ glycine, C¹⁴ alanine, C¹⁴ tyrosine, C¹⁴ aspartic acid, C¹⁴ glutamic acid, C¹⁴ phenylalanine and C¹⁴ serine was given per os, to make its radioautograph.
3) The quantity of the amino acid absorbed by the posterior division is the same at all the cells.
4) The absorption of the C¹⁴ amino acid is taken place at all the cells of the middle division of the silkgland, but its activity is especially strong at the cells present at all the middle part of the middle division and at the anterior half of the posterior part of the middle division. At the posterior part of the middle division is recognized one boundary-line, before and behind where the absorption ability varies strikingly.
5) The quantitative ratios of the amino acid absorbed by cells of the posterior division for the amino acid absorbed by cells of the middle division vary remarkably by different amino acids.