Role of neuropeptides in sex pheromone production in moths

Sex pheromone biosynthesis in many moth species is controlled by a cerebral neuropeptide, termed pheromone biosynthesis activating neuropeptide (PBAN). PBAN is a 33 amino acid C-terminally amidated neuropeptide that is produced by neuroendocrine cells of the subesophageal ganglion (SEG). Studies of the regulation of sex pheromone biosynthesis in moths have revealed that this function can be elicited by additional neuropeptides all of which share the common C-terminal pentapeptide FXPRL-amide (X = S, T, G, V). In the past two decades extensive studies were carried out on the chemical, cellular and molecular aspects of PBAN and the other peptides (termed the pyrokinin (PK)/PBAN family) aiming to understand the mode of their action on sex pheromone biosynthesis. In the present review we focus on a few of these aspects, specifically on the: (i) structure-activity relationship (SAR) of the PK/PBAN family, (ii) characterization of the PK/PBAN receptor and (iii) development of a novel strategy for the generation of PK/PBAN antagonists and their employment in studying the mode of action of the PK/PBAN peptides.     

Juvenile hormones: Their role in the regulation of the pheromonal communication system of the armyworm moth,Pseudaletia unipuncta

Recently, much effort has been devoted to the elucidation of the neuro-endocrine mechanisms regulating the biosynthesis and emission of sex pheromones in the Lepidoptera. The available data indicate that the hormonal mechanisms involved vary considerably among species. For example, compelling evidence that juvenile hormones (JH) play a role in the control of sex pheromone production has been presented only for the armyworm moth, Pseudaletia unipuncta. In this species, females that are allatectomized at emergence neither produce nor release pheromone, but both activities are restored following replacement therapy with synthetic JH. However, injection of synthetic JH into neck-ligated females does not induce pheromone biosynthesis, whereas treatment with either a brain homogenate or synthetic PBAN results in a rise in the pheromone titer. These results indicate that the role played by JH is an indirect one and that the tropic factor is a PBAN-like substance. Studies on in vitro JH biosynthesis by isolated corpora allata of P. unipuncta have shown that the low JH output observed early in the life of adult females coincides with the absence of both calling behavior and pheromone production. The subsequent increase in the rates of JH biosynthesis correlates with the onset of pheromone production and release. We have therefore proposed that JH titers must pass a threshold level before the circadian release of PBAN and calling behavior can begin. Furthermore, recent experiments suggest that the continuous presence of JH is necessary for calling behavior to be maintained once initiated. Lastly, we present data suggesting a role for JH or JH acids in the receptivity of P. unipuncta males to the female sex pheromone. © 1994 Wiley-Liss, Inc.     

RNA interference of pheromone biosynthesis-activating neuropeptide receptor suppresses mating behavior by inhibiting sex pheromone production in Plutella xylostella (L.)

Sex pheromone production is regulated by pheromone biosynthesis-activating neuropeptide (PBAN) in many lepidopteran species. We cloned a PBAN receptor (Plx-PBANr) gene from the female pheromone gland of the diamondback moth, Plutella xylostella (L.). Plx-PBANr encodes 338 amino acids and has conserved structural motifs implicating in promoting G protein coupling and tyrosine-based sorting signaling along with seven transmembrane domains, indicating a typical G protein-coupled receptor. The expression of Plx-PBANr was found only in the pheromone gland of female adults among examined tissues and developmental stages. Heterologous expression in human uterus cervical cancer cells revealed that Plx-PBANr induced significant calcium elevation when challenged with Plx-PBAN. Female P. xylostella injected with double-stranded RNA specific to Plx-PBANr showed suppression of the receptor gene expression and exhibited significant reduction in pheromone biosynthesis, which resulted in loss of male attractiveness. Taken together, the identified PBAN receptor is functional in PBAN signaling via calcium secondary messenger, which leads to activation of pheromone biosynthesis and male attraction.     

Discovery of a linear lead antagonist to the insect pheromone biosynthesis activating neuropeptide (PBAN)

We report the discovery of a linear lead antagonist for the insect pheromone biosynthesis activating neuropeptide (PBAN) which inhibits sex pheromone biosynthesis in the female moth Heliothis peltigera. Two approaches have been used in attempting to convert PBAN agonists into antagonists. The first involved omission of the C-terminal amide and reduction of the sequence from the N-terminus in a linear library based on PBAN 1-33NH(2.) The second involved replacement of L amino-acids by the D hydrophobic amino acid D-Phe in a linear library based on PBAN28-33NH(2.) Screening of the two libraries for pheromonotropic antagonists resulted in the disclosure of one compound out of the D-Phe library (Arg-Tyr-Phe-D-Phe-Pro-Arg-Leu-NH(2)) which inhibited sex pheromone production by 79 and 64% at 100 pmol in two moth colonies and exhibited low agonistic activity. Omission of the C-terminal amide in PBAN 1-33NH(2) and its shorter analogs did not lead to the discovery of an antagonistic compound.     

Tissue localization and partial characterization of pheromone biosynthesis activating neuropeptide inAchaea janata

Female sex pheromone production in certain moth species have been shown to be regulated by a cephalic endocrine peptidic factor: pheromone biosynthesis activating neuropeptide (PBAN), having 33 amino acid residues. Antisera against syntheticHeliothis zea-PBAN were developed. Using these polyclonals, immunoreactivity was mapped in the nervous system ofAchaea janata. Three distinct groups of immunopositive secretory neurons were identified in the suboesophageal ganglion; and immunoreactivity was observed in the corpora cardiaca, thoracic and in the abdominal ganglia. From about 6000 brain sub-oesophageal ganglion complexes, the neuropeptide was isolated; and purified sequentially by Sep-pak and reversed phase high performance liquid chromatographic methods. Identity of purified PBAN fraction was confirmed with polyclonal antibody by immunoblotting. Molecular mass of the isolated peptide was determined by matrix-assisted laser desorption/ionization mass spectrometry, and was found to be 3900 Da, same as that of knownH. zea-PBAN. Radiochemical bioassay confirmed the pheromonotropic effect of the isolated neuropeptide in this insect     

Pheromonotropic stimulation of moth pheromone gland cultures in vitro

The direct neurohormonal control of pheromone biosynthesis by pheromone biosynthesis activating neuropeptide (PBAN) was demonstrated in Helicoverpa (Heliothis) spp. using pheromone gland cultures in vitro. Pheromone gland activation involved the de novo production of the main pheromone component (Z)-11-hexadecenal as revealed by radio-TLC, radio-HPLC, and radio-GC. Activation was found to be a specific response attributed to pheromone gland cultures alone. Specificity of pheromonotropic activation was demonstrated to be limited to nervous tissue extracts. A sensitive and specific radioimmunoassay was developed using [³H]-PBAN, and the spatial and temporal distribution of PBAN-immunore-activity was studied. PBAN-immunoreactivity in brain complexes was found throughout the photoperiod and in all ages. From the distribution of PBAN-immunoreactivity it appears that PBAN release is affected by photoperiod. Pheromone gland cultures were found to be competent to pheromone production irrespective of age and photoperiod. Therefore, the neuroendocrine control of pheromone production operates at the level of neuropeptide synthesis and/or release and not at the level of the target tissue itself. The involvement of cyclic-AMP as a second messenger system was demonstrated. Brain extracts and PBAN were shown to stimulate dose- and time-dependent changes in intracellular cyclic-AMP levels. The role of cyclic-AMP in this mechanism was further verified by the ability of cyclic-AMP mimetics to mimic the pheromonotropic effect of brain extracts and PBAN. However, dose-response studies using PBAN and a hexapeptide C-terminal fragment of PBAN suggested that PBAN induces a two mechanism response, one occurring at low PBAN concentrations (high affinity receptor) and another at higher PBAN concentrations (low affinity receptor). Further evidence indicating a dual receptor system was obtained with the observation that the active phorbol ester (phorbol-12-myristate 13-acetate), the diacyl-glycerol analog (1,2-dioleolyl-sn-glycerol), and the intracellular calcium ionophore (ionomycin) mimicked the physiological action of PBAN and that lithium chloride had a pheromonostatic effect. The results indicate that pheromone glands also possess receptors that are linked to inositol phosphate hydolysis. © 1994 Wiley-Liss, Inc.     

Regulation of pheromone production in virgin and mated females of two tortricid moths

Sex pheromone titers in females of two tortricid moths, Epiphyas postvittana and Planotortrix octo, did not significantly vary between the scotophase and photophase. Pheromone production in these two species is controlled by a factor located in the head of the respective females, probably the pheromone biosynthesis-activating neuropeptide (PBAN). Unlike that reported for the related tortricid, Argyrotaenia velutinana, the bursa copulatrix in female E. postvittana and P. octo does not appear to contain a factor that stimulates pheromone production. After mating, female E. postvittana permanently shut down pheromone production. In contrast, pheromone titer in mated P. octo females is reduced to a level approximately half that of similar-age virgins. While the abdominal nervous system is involved in the inactivation of pheromone production in mated E. postvittana females and probably acts to stop release of PBAN from the corpora cardiaca, the abdominal nervous system is not involved in effecting the decreased pheromone titers of mated P. octo females. It is possible that in the latter species, a humoral factor(s) is responsible for effecting the decreased pheromone titers, possibly through affecting the release of PBAN from the corpora cardiaca. Bioassaying head extracts allowed changes in PBAN titer in female E. postvittana to be inferred. PBAN titers remain roughly constant in virgins but increase after mating. This suggests that PBAN is biosynthesized throughout the life of an adult virgin female at approximately the same rate as it is released. Furthermore, it appears that the decline in pheromone titer observed in older E. postvittana females is probably due to a decline in competency of the gland to produce pheromone rather than to a decrease in PBAN titer in older females. © 1994 Wiley-Liss, Inc.     

Ant Trail Pheromone Biosynthesis Is Triggered by a Neuropeptide Hormone

Our understanding of insect chemical communication including pheromone identification, synthesis, and their role in behavior has advanced tremendously over the last half-century. However, endocrine regulation of pheromone biosynthesis has progressed slowly due to the complexity of direct and/or indirect hormonal activation of the biosynthetic cascades resulting in insect pheromones. Over 20 years ago, a neurohormone, pheromone biosynthesis activating neuropeptide (PBAN) was identified that stimulated sex pheromone biosynthesis in a lepidopteran moth. Since then, the physiological role, target site, and signal transduction of PBAN has become well understood for sex pheromone biosynthesis in moths. Despite that PBAN-like peptides (∼200) have been identified from various insect Orders, their role in pheromone regulation had not expanded to the other insect groups except for Lepidoptera. Here, we report that trail pheromone biosynthesis in the Dufour''s gland (DG) of the fire ant, Solenopsis invicta, is regulated by PBAN. RNAi knock down of PBAN gene (in subesophageal ganglia) or PBAN receptor gene (in DG) expression inhibited trail pheromone biosynthesis. Reduced trail pheromone was documented analytically and through a behavioral bioassay. Extension of PBAN''s role in pheromone biosynthesis to a new target insect, mode of action, and behavioral function will renew research efforts on the involvement of PBAN in pheromone biosynthesis in Insecta.     

Juvenile hormone induction of pheromone gland PBAN-responsiveness in Helicoverpa armigera females

The maturation of corpora allata (CA) and the competence of pheromone glands in the adult moth Helicoverpa armigera, are both age-related and appear to be correlated. Sex pheromone glands of pharate adults do not produce sex pheromone independently, nor do they respond to exogenous PBAN. Newly emerged moths produce significantly less pheromone than day one moths. JH (juvenile hormone) II was found to be the main JH form produced by CA in vitro. JH II primed pheromone glands of pharate adults to respond to PBAN. In addition, injection or topical application of JH II to newly-emerged females induced pheromone production in the presence of PBAN. Our findings suggest that JH is involved in the initiation of pheromone production of Helicoverpa armigera.     

Endogenous control of circadian rhythms of pheromone production in the turnip moth, Agrotis segetum

The circadian variation of pheromone production in the turnip moth, Agrotis segetum, was characterized by quantifying (Z)-7-dodecenyl acetate (Z7-12:OAc), the most abundant pheromone component produced by female turnip moth, at different times of day. Under 17:7 h light-dark cycle (LD), the peak of Z7-12:OAc production occurred around 4 h into the scotophase, while there was very little pheromone production during the photophase. When females were maintained under constant darkness (DD), the periodicity of pheromone production was sustained for 3 consecutive days. Furthermore, the rhythm in pheromone production could be entrained to a shifted LD. These results demonstrate that the pheromone production in the turnip moth is regulated endogenously by a circadian clock. To understand how the circadian rhythm of pheromone production is generated, circadian variation of pheromone- biosynthesis-activating neuropeptide (PBAN)-like activity in the brain-suboesophageal ganglion complexes (Br-SOG), hemolymph, and ventral nerve cord (VNC) was also examined. Under both LD and DD, only the VNC displayed a circadian variation in the PBAN-like activity, which was significantly higher during the late-photophase than that in the scotophase. In addition, the present study showed that removal of VNC in isolated abdomen did not affect PBAN stimulation of pheromone production, while severing the VNC impaired normal pheromone production. The role of Br-SOG, VNC, and hemolymph in the regulation of the periodicity of pheromone production is discussed.     

Involvement of calcineurin in the signal transduction of PBAN in the silkworm, Bombyx mori (Lepidoptera)

In several moth species sex pheromone production in the pheromone gland is regulated by a neurohormone, pheromone biosynthesis activating neuropeptide (PBAN). In Bombyx mori it is suggested that PBAN, after binding to the cell-surface receptor, primarily activates a plasma membrane receptor-activated Ca2+ channel to increase cytosolic levels of Ca2+, and Ca2+/calmodulin complex directly or indirectly activates a phosphoprotein phosphatase, which in turn elicits activation of acyl CoA reductase (the key enzyme under PBAN control) through dephosphorylation, resulting in pheromone (bombykol) production. The effect of cyclosporin A (CsA) and FK 506, specific inhibitors of calcineurin (phosphoprotein phosphatase 2B) was studied on the sex pheromone production, in B. mori. The in vitro experiments showed that both chemicals exerted a dose-dependent inhibitory action when they were co-incubated with TKYFSPRL amide (Hez-PBAN fragment peptide). Practically, no difference was detected between the two chemicals in the tested doses (0.025-1250 microM). When effects of CsA or FK 506 were studied on cell-free production of bombykol by using microsomal fraction no inhibition was detected. Since microsomal fraction contains the acyl CoA synthetase, the rate-limiting acyl CoA reductase and the precursor, bombykol is produced if supplied with CoA, ATP and NADPH. Thus, the inhibitory action of CsA and FK506 under in vitro conditions should occur before the step of acyl group reduction and the effect is likely to be attributable to the inhibition of calcineurin in the signal transduction cascade mechanism of PBAN, in B. mori. The existence of calcineurin in the pheromone gland by using Western blot analysis is also demonstrated.     

Temporal distribution of PBAN‐like immunoreactivity in the hemolymph of Mamestra brassicae females in relation to sex pheromone production and calling behavior

A direct enzyme‐linked immunosorbent assay has been developed and applied to the analysis of PBAN immunoreactivity in female hemolymph of the cabbage armyworm, Mamestra brassicae. PBAN‐IR determinations have been carried out with third scotophase insects at different times of the photoperiod. The rhythm of calling and the pattern of pheromone production by third scotophase females at different times of the photoperiod have also been determined. PBAN‐IR and calling are well correlated. However, whereas pheromone titers decrease, both PBAN‐IR levels and percentage of calling females remain high in the last hours of the scotophase. These results are discussed in the context of the regulation of sex pheromone biosynthesis in M. brassicae. Arch. Insect Biochem. Physiol. 40:80–87, 1999. © 1999 Wiley‐Liss, Inc.     

Termination of sex pheromone production in mated females of the silkworm moth

A mating duration of more than 6 h was necessary to permanently terminate the production of the sex pheromone (bombykol) in the silkworm moth, Bombyx mori L. (Lepidoptera: Bombycidae), although the female formed a bursa copulatrix including a spermatophore and laid fertilized eggs even after mating for only 0.5 h. The 6-h mated female again produced bombykol if given an injection of synthetic pheromonotropic neuropeptide (PBAN), which is known to activate pheromone biosynthesis in a virgin female. Extracts of brain-suboesophageal ganglion (SG) complexes, which were removed from 6- and 24-h mated females, showed strong pheromonotropic activities. These results indicated that the pheromone gland of the mated female maintained its ability to biosynthesize bombykol; however, it could not produce pheromone due to a suppression of PBAN secretion from the SG. Furthermore, bombykol titers did not decrease after mating in females with a transected ventral nerve cord, even after the injection of a spermatophore extract, suggesting that the suppression of PBAN secretion was mediated by a neural signal and not by a substance in the spermatophore. The mated females accumulated (10E, 12Z)-10,12-hexadecadienoic acid, a precursor of bombykol biosynthesis, in their pheromone glands as did decapitated females. © 1996 Wiley-Liss, Inc.     

Stimulation of sex pheromone production by proteinaceous extracts of the bursa copulatrix in the redbanded leafroller moth

Pheromone biosynthesis in the redbanded leafroller moth, Argyrotaenia velutinana, was stimulated by homogenates of the bursa copulatrix. Although pheromonotropic activity was also extractable from the ovary, the activity of pheromone biosynthesis activating neuropeptide (PBAN) or bursa extracts was not impaired in isolated abdomens by removal of the ovary. Response to the bursa extracts was dependent on the dose administered and the time of incubation. Amounts of pheromone present in adult females of different ages appeared to be correlated with the extractable amount of pheromonotropic activity from their bursa copulatrix. Decapitation did not result in the suppression of burse factor production. Homogenates of the bursa elicited similar effects in both isolated gland and isolated abdomen incubations, but the brain neuropeptide, PBAN, was less active in the former than in the latter. Bursa extracts stimulated pheromone production in isolated abdomen incubations deprived of the bursa copulatrix, but PBAN did not. Loss of activity of bursa homogenates after treatment with either pronase E or carboxypeptidase Y indicated that the pheromonotropic factor is a proteinaceous substance. The mechanism through which pheromone production is regulated in redbanded leafroller moths is discussed. © 1992 Wiley-Liss, Inc.     

Regulation of pheromone inhibition in mated females of Choristoneura fumiferana and C. rosaceana

In the spruce budworm, Choristoneura fumiferana, and the obliquebanded leafroller, C. rosaceana, mating significantly depressed pheromone production after 24 h. On subsequent days, the pheromone titre increased slightly in C. fumiferana, but not in C. rosaceana. No pheromonostatic activity was associated with male accessory sex gland (ASG) extracts, 20-hydroxy-ecdysone or hemolymph taken from mated females. However, pheromone production in mated females was not suppressed when the ventral nerve cord (VNC) was transected prior to mating, indicating that an intact VNC is required to permanently switch off pheromone production after mating. As suggested for other moth species, the presence of sperm in the spermatheca probably triggers the release of a signal, via the VNC, to inhibit pheromone production. The fact that in both species the brain-suboesophageal ganglion (Br-SEG) of mated females contains pheromonotropic activity and that their pheromone glands may be stimulated by the synthetic pheromone-biosynthesis-activating-neuropeptide (PBAN) or a brain extract supports the hypothesis that the neural signal prevents the release of PBAN into the hemolymph rather than inhibiting its biosynthesis. Therefore, we speculate that following the depletion of sperm in the spermatheca, the neural signal declines and is less effective in preventing the release of PBAN, thereby stimulating the resumption of pheromone production, as seen in mated C. fumiferana females. In a previous study, mating was shown to induce a significant rise in the juvenile hormone (JH) titre of both Choristoneura female moths, suggesting that post-mating pheromone inhibition may be under hormonal regulation. However, following topical applications or injections of the juvenile hormone analogue (JHA) and JH II into virgins, the pheromone only declined significantly 48 h after treatment in C. rosaceana. This suggests that the significant rise in the hemolymph JH titre after mating in C. rosaceana females plays a role in keeping the pheromone titre consistently low throughout their reproductive life. These findings will be discussed in relation to the different life histories of the two Choristoneura species.     

The Bombyx mori sex pheromone biosynthetic pathway is not mediated by cAMP

In most moths, sex pheromone production is regulated by pheromone biosynthesis-activating neuropeptide (PBAN). How the extracellular PBAN signal is turned into a biological response has been the focus of numerous studies. In the classical scheme of signal transduction, activated G proteins relay the extracellular signal to downstream effector molecules such as calcium channels and adenylyl cyclase. The role of calcium in PBAN signaling has been clearly demonstrated, but the possible involvement of cAMP is not as straightforward. While cAMP has been shown to be necessary for PBAN signaling in most heliothine species, there has been no definitive demonstration of its role in Bombyx mori. To address this question, we used degenerate RT-PCR to clone two Gs subunits, designated P50Gs1 and P50Gs2, from B. mori pheromone gland (PG) cDNAs. The two Gs proteins were expressed in all tissues examined and were not up-regulated in accordance with adult eclosion. Even though two bands corresponding to the approximate molecular weights of P50Gs1 and P50Gs2 were detected in PG homogenates, the Gs antagonist, NF449, had no effect on sex pheromone production. Furthermore, no changes in the intracellular cAMP levels were detected following PBAN stimulation.     

Pheromonotropic and pheromonostatic activity in moths

Pheromone biosynthesis in many species of moths requires a pheromonotropic neurosecretion, the pheromone biosynthesis activating neuropeptide (PBAN), from the brain-subesophageal ganglion-corpora cardiaca complex. Some investigators suggest that PBAN is released into the hemolymph and acts directly on sex pheromone glands (SPG) via a Ca⁺⁺/calmodulin-dependent adenylate cyclase. Others suggest, however, that PBAN acts via octopamine that is released by nerves from the terminal abdominal ganglion innervating the SPG. These findings suggest that there are controversies on the mode of action of PBAN and other pheromonotropic factors, sometimes even within the same species. Mating in many insects results in temporary or permanent suppression of pheromone production and/or receptivity. Such a suppression may result from physical blockage of the gonopore or deposition of pheromonostatic factor(s) by the male during copulation that result in suppressed pheromone production and/or receptivity in females either directly or by a primer effect. In several species of insects, including moths, a pheromonostatic factor is transferred in the seminal fluid of males. Similar to the controversies associated with the pheromonotropic activity of PBAN, sometimes even within the same species, there appear to be controversies in pheromonostasis in heliothines as well. This paper reviews these conflicting findings and presents some data on pheromonostatic and pheromonotropic activity in Heliothis virescens that support and conflict with current information, raising further questions. Answers to some of the questions are partly available; however, they remain to be answered unequivocally. © 1994 Wiley-Liss, Inc.     

The distribution of PBAN (pheromone biosynthesis activating neuropeptide)-like immunoreactivity in the nervous system of the gypsy moth,Lymantria dispar

The production of sex pheromone in many moths is regulated by the neuropeptide PBAN (pheromone biosynthesis-activating neuropeptide). Studies in a number of species have shown that pheromone production can be linked to a hemolymph factor and that continuity in the ventral chain of ganglia is not required. However, it has recently been shown that production of pheromone in the gypsy moth, Lymantria dispar, is largely prevented in females with a transected ventral nerve cord (VNC). To begin to understand the cellular basis for this dependence on the VNC, we sought to determine the distribution of PBAN in the central nervous system and its neurohemal sites, including those associated with the VNC. Using an antiserum to L. dispar-PBAN in immunocytochemical methods, we have mapped the distribution of PBAN-like immunoreactivity (PLI). PLI is found in three clusters of ventral midline somata in the subesophageal ganglion (SEG), in three clusters of midline cells in each segmental ganglion, and in bilateral pairs of cells located posterolaterally in each abdominal ganglion. The SEG cells comprise both interneurons, with endings in the neuropil of each segmental ganglion, as well as neurosecretory cells, with endings in the retrocerebral complex and in an unusual neurohemal structure near the anterior aspect of the SEG. The latter structure, which we have named the corpus ventralis, receives axons from the two anterior clusters of cells in the SEG. In the abdominal ganglia, the posterolateral clusters of cells have immunoretroreactive axons exiting the ganglia via the ventral nerves. Endings of these axons reach the perivisceral organ in the next posterior ganglion and pass anteriorly into the median nerve, forming additional varicose endings. We did not detect PLI in the terminal nerve. Thus, our findings raise the possibility that the requirement for an intact VNC in pheromone production reflects a role for descending regulation of neurosecretory cells in the segmental ganglia. Arch. Insect Biochem. Physiol. 34:391–408, 1997. Published 1997 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

昆虫神经肽PBAN的细胞内信号转导

昆虫性信息素多数为长链的不饱和醇、醋酸酯、醛或酮类,链长一般为10-20碳,主要在性信息素腺体内由乙酰辅酶A经过脂肪酸合成、碳链缩短、去饱和以及碳酰基的还原修饰等步骤合成的;而性信息素合成激活肽(pheromone biosynthesis activating neuropeptide,PBAN)是由昆虫食管下神经节中的部分神经细胞合成和分泌的神经肽,通常由33个氨基酸组成,在C-末端有一个相同的五肽序列,主要调控性信息素的生物合成。有关PBAN的细胞内信号转导是近几年的研究热点,研究显示 PBAN首先与性信息素腺体细胞表面的G蛋白偶联受体结合,随后依据昆虫种类的不同,其细胞内信号转导方式主要有三种:(1)以cAMP信号传导途径进行信号转导;(2)以cAMP和磷脂酰肌醇信号传导途径共同进行信号转导;(3)主要以Ca2 为第二信使进行信号传导。