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Proc Natl Acad Sci U S A. 1974 Apr; 71(4): 1050–1054.
PMCID: PMC388159

Purification and Characterization of the Hormone Initiating Sexual Morphogenesis in Volvox carteri f. nagariensis Iyengar


In Volvox carteri f. nagariensis male spheroids secrete into the medium a sexual hormone which controls the initiation of the developmental pathway leading to the formation of sexual embryos. In the absence of the hormone asexual embryos are formed. Analysis of the highly purified hormone indicates that it is a glycoprotein of 27,500-30,000 daltons, composed of one peptide chain, which has a typical composition except for a relatively low content of tryptophan. The glycosidic moiety, which accounts for about 45% of the weight of the molecule, consists of pentoses, hexoses, and amino hexoses. In the bioassay the highly purified hormone stimulates 100% formation of sexual embryos at a concentration of 10-10 g/liter and 14.4% sexual embryos at 10-11 g/liter (3 × 10-16 M). The activity is remarkably thermostable and resistant to different denaturing procedures.

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  • Darden WH., Jr Sexual differentiation in Volvox aureus. J Protozool. 1966 May;13(2):239–255. [PubMed]
  • Starr RC. Cellular differentiation in Volvox. Proc Natl Acad Sci U S A. 1968 Apr;59(4):1082–1088. [PMC free article] [PubMed]
  • Kochert G. Differentiation of reproductive cells in Volvox carteri. J Protozool. 1968 Aug;15(3):438–452. [PubMed]
  • Ely TH, Darden WH. Concentration and purification of the male-inducing substance from Volvox aureus M5. Microbios. 1972 Jan;5(17):51–58. [PubMed]
  • Andrews P. The gel-filtration behaviour of proteins related to their molecular weights over a wide range. Biochem J. 1965 Sep;96(3):595–606. [PMC free article] [PubMed]
  • Hedrick JL, Smith AJ. Size and charge isomer separation and estimation of molecular weights of proteins by disc gel electrophoresis. Arch Biochem Biophys. 1968 Jul;126(1):155–164. [PubMed]
  • Weber K, Osborn M. The reliability of molecular weight determinations by dodecyl sulfate-polyacrylamide gel electrophoresis. J Biol Chem. 1969 Aug 25;244(16):4406–4412. [PubMed]
  • Bretscher MS. Major human erythrocyte glycoprotein spans the cell membrane. Nat New Biol. 1971 Jun 23;231(25):229–232. [PubMed]
  • MARTIN RG, AMES BN. A method for determining the sedimentation behavior of enzymes: application to protein mixtures. J Biol Chem. 1961 May;236:1372–1379. [PubMed]
  • Rao DR, Beyreuther K, Jaenicke L. A comparative study of pig and sheep-brain glutamine synthetases: tryptic peptides and thiol groups. Eur J Biochem. 1973 Jun 15;35(3):582–592. [PubMed]
  • Machlis L. The coming of age of sex hormones in plants. Mycologia. 1972 Mar-Apr;64(2):235–247. [PubMed]
  • Machlis L, Nutting WH, Williams MW, Rapoport H. Production, isolation, and characterization of sirenin. Biochemistry. 1966 Jul;5(7):2147–2152. [PubMed]
  • Müller DG, Jaenicke L, Donike M, Akintobi T. Sex attractant in a brown alga: chemical structure. Science. 1971 Feb 26;171(3973):815–817. [PubMed]
  • Barksdale AW. Sexual hormones of Achlya and other fungi. Science. 1969 Nov 14;166(3907):831–837. [PubMed]
  • Pall ML. Sexual induction in Volvox carteri. A quantitative study. J Cell Biol. 1973 Oct;59(1):238–241. [PMC free article] [PubMed]

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