Yasutoshi Katakura

Isolation and properties of androgenic gland hormone from the terrestrial isopod, Armadillidium vulgare

Abstract The androgenic gland hormone (AGH) is known to control sex differentiation in crustaceans. AGH was purified from isolated androgenic glands (AGs) of the male isopod Armadillidium vulgare by three steps of reverse-phase high performance liquid chromatography (RP-HPLC) and its chemical properties were examined. The purified AGH-active fraction showed masculinizing activity when 38 pg of this preparation was injected into a young female of the same species. Only 160 ng of the material was obtainable from 2000 animals at about an 11% rate of recovery. The elution of AGH activity by molecular sieve HPLC indicated that molecular weight of AGH was 11,000 ∼ 13,000. AGH was inactivated by treatment with trypsin or by reductive carboxymethylation. The AGH activity was not affected by heat treatment at 100°C for 3 min. These results indicated that AGH was a heat-stable protein with disulfide bond(s).

Masculinization of females of the isopod crustacean, Armadillidium vulgare, following injections of an active extract of the androgenic gland

Injections of 64 U of an active extract of the androgenic gland into young females of Armadillidium vulgare induced masculinization of the external sexual characteristics and transformation of the internal female reproductive organs into testes, seminal vesicles, and vasa deferentia. Following injections of 10-U doses, the internal organs were hardly affected in 8 of 10 females although the external characteristics underwent masculinization.

Endocrine and genetic control of sex differentiation in the Malacostracan Crustacea

Summary Sex differentiation in Malacostraca is controlled by hormone secreted from the androgenic glands. Experimentally induced sex inversions in isopods and amphipods proved that the genetic female and male possess primordia of the androgenic glands, gonads, and gonoducts, along with sexual characteristics of both sexes. During the sensitive period, the presence or absence of androgenic gland hormone (AGH) affects the differentiation of these primordia. Genetic control of the development of androgenic gland primordium seems to be brought about assuming of the following: 1. Both genetic female and male possess gene(s) (AGH-G) responsible for the AGH-synthesis situated on the homologous loci of the sex chromosomes and/or on the autosomes. 2. The gene(s) are activated spontaneously with the lack of inhibition of the major sex factor carried by the W or X chromosome. The W and X factors are hypostatic to major sex factor carried by the Y chromosome. The Z factor does not seem to influence sex differentiatio...

Vitellogenin synthesis by fat body and ovary in the terrestrial isopod, Armadillidium vulgare

Vitellogenin synthesis in Armadillidium vulgare was investigated in tissue cultures. The synthesis of vitellogenin was assayed by the incorporation of [35S]methionine into precipitin with anti-vitellin serum. The forms of synthesized vitellogenin were analyzed by polyacrylamide gel electrophoresis and fluorography. The fat body synthesized vitellogenin and its rate was correlated with the molting cycle: a maximum level at stage D and lower levels at A-C and E of the molting cycle. Four forms of vitellogenin (Vg 1-4) were synthesized; the larger forms (Vg 1-2) were prominent. The ovary also synthesized a slight amount of vitellogenin at the end of the molting cycle. The smaller forms (Vg 3-4) were synthesized under cultured condition. Through vitellogenesis in A. vulgare, the fat body must be the principal site of vitellogenin synthesis. Most vitellogenin may be transported from the fat body to the ovary through hemolymph at stage D of the molting cycle.

An Immunoassay for the Androgenic Gland Hormone of the Terrestrial Isopod, Armadillidium vulgare

Summary Antiserum was raised in a rabbit against the purified androgenic gland hormone (AGH) of Armadillidium vulgare. The specificity of the antiserum was confirmed by immunoblotting and by absorption of the biological activity of AGH. The immunological activity measured by ELISA correlated well with the biological activity of AGH. It is therefore possible to measure AGH by immunoassay. The immunoassay, which is time-saving and avoids the handling problems of the bioassay was used to measure seasonal variation of AGH content in male reproductive organs. Lack of immunological crossreactivity between preparations from different isopod species supported former results on biological species-specificity.

ANDROGENIC GLAND HORMONE AND DEVELOPMENT OF OVIDUCTS IN THE ISOPOD CRUSTACEAN, ARMADILLIDIUM VULGARE

When androgenic glands from mature males were implanted into females of Armadillidium vulgare during the 3rd, 4th and 5th instars, oviducts developed in 14.3, 37.9 and 85.2% of the masculinized females, respectively. These results show that development of the rudimentary oviducts is inhibited by the androgenic gland hormone in very young females. Development of the oviduct seems to be determined at a critical period in about the 4th instar and after this, the hormone has little inhibitory effect.