Juvenile hormone binding proteins of termites detected by photoaffinity labeling: Comparison of Zootermopsis nevadensis with two rhinotermitids

Abstract

The hemolyrnph of each caste of the primitive dampwood termite Zootermopsis nevadensis (Isoptera, Termopsidae, Termopsinae) contains a high molecular mass lipoprotein which functions as a specific, high affinity carrier for juvenile hormone (JH) Ill, as detected by JH Ill-displaceable covalent modification by the tritium-labeled photoaffinity analog ( INTRODUCTIONJuvenile hormones are key control elements in the physiology of insect growth, development, reproduction, and caste control in social insects [1,2]. Luscher [3] underscored the fact that caste control in termites occurs as a result of changes in the JH* titers which are modulated by the environment. This role of JH and JH mimics has been demonstrated in a number of termite species, including lower termites, e.g., Knlotermes fluvicollis [4], &ticdifermesfiuvipes [5,6], and Zootermopsis nevudensis [7], and in the higher termites, e.g., Nnsutitermes exitiosus [S] and Macrotermes michaelseni 191.

Effects of juvenile hormone III on Reticulitermes flavipes: changes in hemolymph protein composition and gene expression

“…These two proteins included one hexamerin ($85 kDa) and one vitellogenin ($220 kDa). These findings suggest that the high mass lipophorin-like hJHBP identified previously (Okot-Kotber and Prestwich, 1991a;Fan et al, 2004) may be a vitellogenin. Finally, the expression of vitellogenin-and hexamerinencoding genes during JH-induced presoldier differentiation was investigated.…”

Life history and development ‐ a framework for understanding developmental plasticity in lower termites

“…After its release into the haemolymph, the extremely lipophilic JH molecule must be bound to transport proteins in order to reach target organs and to remain protected against degradation by JH esterases and/or JH epoxide hydrolases (reviewed by Goodman & Granger, 2005). JH binding proteins have been identified by photoaffinity labeling in haemolymph of the rhinotermitids Reticulitermes flavipes, Coptotermes formosanus and the termopsid Zootermopsis nevadensis (Okot‐Kotber & Prestwich, 1991 a , b ). While these proteins bind JH with high affinity, two general transport and storage proteins, hexamerin 1 (Hex‐1) and hexamerin 2 (Hex‐2) have recently emerged as major candidates for regulators of soldier development in the rhinotermitid Reticulitermes flavipes .…”