Isolation and characterization of a high molecular weight JH‐III transport protein in the hemolymph of locusta migratoria

Abstract

Acknowledgments: We gratefully acknowledge the gift of (1OR)-JH-Ill from Dr. D.A. Schooley (Zoecon. Corp., Palo Alto, CA), and the Small Animal Center (Wageningen) for help with the immunization and bleeding of the rabbits. We thank Dr. M. Khan for critically reading the manuscript and Mr. J.C. Rigg for checking the English.

Identification, characterization, and developmental profile of a high molecular weight, juvenile hormone‐binding protein in the hemolymph of the migratory grasshopper, Melanoplus sanguinipes

“…The Kd value (2.1 nM) obtained in our studies for the purified hemolymph JHBP in M. sanguinipes is similar to that of L. migratoria hemolymph JHBP (3.7 nM) (Koopmanschap and de Kort, 1988). These values fall in the range reported for hemolymph high-affinity JH-binding proteins in other insects (see Trowell, 1992).…”

“…Koopmanschap and de Kort (1988) found that the JHBP in L. migratoria contains lipid moieties, but did not apparently check for the presence of carbohydrate.…”

“…This is in agreement with a report by de Bmijn et al (1986) that the binding protein of L. migratoria had a M , of 575,000 and was composed of six identical subunits (M, = 81,000). Koopmanschap and de Kort (1988) further characterized this protein and, using slightly different methodology, found it to be a very high density lipoprotein with a M, of 566,000 and composed of six identical subunits whose M, was 77,000. These observations differ from those of Wisniewski (1989) who reported on the basis of an autoradiographic study that the hemolymph of L. migratoria contained five JHBP species with M, of 666,000,500,000,450,000 and 390,000 (PI 4.6 and 5.1).…”

Growth of the male accessory gland in adult locusts: Roles of juvenile hormone, JH esterase, and JH binding proteins

“…However, substantial levels of JHBP, a high affinity JH binding protein previously identified in locust hemolymph (De Bruijn et al, 1986;Koopmanschap and de Kort, 1988) and fat body (Braun et al, 1995), were detected in accessory gland extracts by immunoblotting and by JH binding after fractionation on a heparin-agarose column (unpublished data). The reason for this discrepancy was identified as a strong JH degradative activity.…”

Sequence of the Hexameric Juvenile Hormone-binding Protein from the Hemolymph of Locusta migratoria

“…JHBP is present in the hemolymph of both sexes and shows only slight changes in abundance during the fourth and fifth larval instars and early adult life (10). Its 4.3-kb mRNA is the largest mRNA yet identified for any hexamerin, with 2 kb of 3Ј-untranslated sequence, and it is possible that sequences at the 3Ј end of the message, through recognition by specific proteins, may be responsible for maintenance of JHBP levels during times when variations occur in factors such as hormones or nutrition (45).…”