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At least 1,189 records · Page 66Linked to original sources

PubMed1997

Position one analogs of the Saccharomyces cerevisiae tridecapeptide pheromone.

Analogs of the Saccharomyces cerevisiae alpha-mating factor [WHWLQLKPGQPMY], in which a variety of residues replaced Trp1 were synthesized and assayed for biological activity and receptor affinity. Analogs containing Gly or Leu or many different aromatic residues in position 1 of the peptide exhibited bioactivity in a growth arrest assay slightly greater than, or equal to, that of the parent pheromone, whereas the Glu1 and Lys1 analogs exhibited significantly lower bioactivity. Analogs with an aromatic replacement at position 1 had 3- to 6-fold lower receptor affinity than the parent peptide, whereas analogs with a hydrophilic residue at the N-terminus exhibited large reductions in receptor affinity with the peptide with Glu in position 1 showing a 120-fold reduction. N alpha-Acetylation had little effect on bioactivity but lowered receptor affinity by 20- to 40-fold. Amidation of the carboxyl terminus resulted in a 10-fold decrease in activity and a 160-fold decrease in receptor affinity. These results indicate that the alpha-factor receptor has a large hydrophobic binding pocket, possibly containing a negatively charged side-chain, which interacts with the N-terminus of alpha-factor. The lack of correlation between activity and binding and several analogs suggests that small residues near the N-terminus of alpha-factor may be very efficient in triggering isomerization of the receptor to its activated state in the first step of the signal transduction pathway.

Gene Expression↗

PubMed1996

Amino acids and peptides. XXIX. Synthesis and antimetastatic effects of peptides and peptide-poly(ethylene glycol) hybrids related to the core sequence of the type III connecting segment domain of fibronectin.

Peptides (H-Glu-Ile-Leu-Asp-Val-NH2, H-Glu-Ile-Leu-Asp-Val-Pro-Ser-Thr-NH2, H-Arg-Glu-Asp-Val-NH2) and their poly(ethylene glycol) (PEG) hybrids related to the core sequence of the type III connecting segment domain of fibronectin A chain were prepared by the solution method or the solid phase method. Their inhibitory effects on the adhesion and migration of B16-BL6 melanoma cells to fibronectin were assessed in vitro, and their therapeutic potency against tumor metastasis were also examined. Anti-adhesive and anti-migrative effects of the synthetic fibronectin-related peptids were superior to those of their PEG hybrids, so we found that the in vitro bioactivity of peptides decreased by PEGylation. In the in vivo assay, we found that the synthetic peptides containing Glu-Ile-Leu-Asp-Val and Arg-Glu-Asp-Val sequences exhibited an inhibitory effect on the experimental metastasis of B16-BL6 melanoma. Of the synthetic peptides, H-Glu-Ile-Leu-Asp-Val-NH2 exhibited the most potent inhibitory effect. Hybrid formation of Arg-Glu-Asp-Val with poly(ethylene glycol) resulted in potentiation of the inhibitory effect of the parent peptides. A mixture composed of PEG hybrids of Glu-Ile-Leu-Asp-Val, Arg-Glu-Asp-Val and Tyr-Ile-Gly-Ser-Arg dramatically inhibited tumor metastasis.

Animals↗

PubMed1997

Comparative bioactivity of atrial and brain natriuretic peptides in an ovine model of heart failure.

1. Whereas many studies have detailed the effects of exogenous atrial natriuretic peptide (ANP) infusions in heart failure, and a limited number have examined the effects of brain natriuretic peptide (BNP), none have directly compared the bioactivity of similar doses of ANP and BNP under standard conditions of impaired cardiac function. We compared the hormonal, haemodynamic and renal effects of 3 h infusions of ANP, BNP and a vehicle control in eight sheep with pacing-induced heart failure (225 beats/min for 8-12 days). 2. Infusion of ANP and BNP increased plasma ANP (P < 0.001) (276 +/- 27 versus control 142 +/- 26 pmol/l) and BNP (P < 0.001) (257 +/- 34 versus control 45 +/- 5 pmol/l) respectively, in association with increased cyclic 3',5'-guanosine monophosphate [control, 40 +/- 6; ANP, 53 +/- 6 (P < 0.05); BNP, 57 +/- 7 nmol/l (P < 0.001)]. Metabolic clearance rate and half-life were similar for both peptides. Infusion of ANP and BNP similarly reduced mean arterial pressure [control, 73.0 +/- 1.6; ANP, 67.6 +/- 1.2 (P < 0.01); BNP, 65.7 +/- 1.7 mmHg (P < 0.001)], left atrial pressure (both P < 0.05) (control, 22.0 +/- 0.7; ANP, 19.9 +/- 1.0; BNP, 19.8 +/- 0.9 mmHg) and peripheral resistance [control, 50.3 +/- 4.1 mmHg l-1 min-1; ANP, 46.0 +/- 2.8 (P < 0.05); BNP, 43.8 +/- 4.5 (P < 0.01)], and increased urine volume (2-3-fold, both P < 0.05), sodium excretion (> 10-fold, both P < 0.01) and haematocrit levels relative to control (both P < 0.05). Infused BNP tended to raise plasma ANP levels (by 28 pmol/l), while ANP increased plasma BNP (by 18 pmol/l). Plasma aldosterone was reduced by approximately 40% by both peptides (both P < 0.05). 3. In conclusion, ANP and BNP are both powerfully, natriuretic, similarly suppress aldosterone and appear equipotent in reducing preload and afterload in this model of pacing-induced heart failure.

Aldosterone↗

PubMed1997

Neutral endopeptidase regulates C-type natriuretic peptide metabolism but does not potentiate its bioactivity in vivo.

C-type natriuretic peptide (CNP) is a newly described 22-amino acid peptide of endothelial and renal cell origin with selective cardiovascular actions. Recent in vitro studies have reported that CNP is the most susceptible of all natriuretic peptides to enzymatic degradation by neutral endopeptidase 24.11 (NEP). The present study was undertaken to define the role of NEP in total and regional CNP metabolism and the modulatory actions of NEP inhibition on the biological actions of CNP. CNP (10 ng x kg(-1) x min(-1)) followed by candoxatrilat (240 microg x kg(-1) bolus and 8 microg x kg(-1) x min(-1)), a potent and selective NEP inhibitor, was administered intravenously to a group of anesthetized mongrel dogs (group 1) to permit calculation of total metabolic clearance rate (MCR); results were compared with those in a group receiving vehicle infusion followed by candoxatrilat (group 2; both groups, n=7). NEP inhibition increased circulating CNP achieved by exogenous infusion and reduced total MCR in group 1. The regional CNP MCRs increased after CNP administration. While the pulmonary MCR did not change during concomitant candoxatrilat infusion, renal MCR was suppressed. Hemodynamic changes were not different between groups. A mild natriuretic and diuretic effect in association with an increase in circulating and urinary ANP levels was not different between groups. Urinary CNP excretion did not change with CNP infusion but markedly increased after NEP inhibition. We conclude that (1) circulating CNP achieved by exogenous CNP infusion is regulated by NEP in vivo, (2) regional MCRs are heterogeneous with NEP inhibition, (3) NEP inhibition does not potentiate acute cardiovascular actions of CNP, and (4) a mild natriuretic and diuretic effect observed with CNP and NEP inhibition may be ANP dependent.

Animals↗

PubMed1998

Design and function of novel osteoblast-adhesive peptides for chemical modification of biomaterials.

Proactive, "next generation" dental/orthopedic biomaterials must be designed rationally to elicit specific, timely, and desirable responses from surrounding cells/tissues; for example, such biomaterials should support and enhance osteoblast adhesion (a crucial function for anchorage-dependent cells). In the past, integrin-binding peptides have been immobilized on substrates to partially control osteoblast adhesion; the present study focused on the design, synthesis, and bioactivity of the novel peptide sequence Lys-Arg-Ser-Arg that selectively enhances heparan sulfate-mediated osteoblast adhesion mechanisms. Osteoblast, but not endothelial cell or fibroblast, adhesion was enhanced significantly (p < 0.05) on substrates modified with Lys-Arg-Ser-Arg peptides, indicating that these peptides may be osteoblast- or bone cell specific. Blocking osteoblast cell-membrane receptors with various concentrations of soluble Arg-Gly-Asp-Ser peptides did not inhibit subsequent cell adhesion on substrates modified with Lys-Arg-Ser-Arg peptides, providing evidence that osteoblasts interact with Arg-Gly-Asp-Ser and with Lys-Arg-Ser-Arg peptides via distinct (i.e., integrin- and proteoglycan-mediated) mechanisms, each uniquely necessary for osteoblast adhesion. The present study constitutes an example of rational design/selection of bioactive peptides, confirms that osteoblast adhesion to substrates can be controlled selectively and significantly by immobilized peptides, and elucidates criteria and strategies for the design of proactive dental/orthopedic implant biomaterials.

Adhesiveness↗

PubMed1989

Cloning of a cDNA encoding porcine brain natriuretic peptide.

Complimentary DNA (cDNA) clones encoding porcine brain natriuretic peptide (BNP) were isolated from a porcine atrial cDNA library. The longest of the cDNA clones (1507 nucleotides) apparently originated from an unprocessed messenger RNA, since the nucleotide sequence encoding BNP-26 was interrupted by an intron of 554 nucleotides. A partial cDNA clone representing processed BNP mRNA was prepared by polymerase chain reaction. A comparison of the sequence of these two cDNAs reveals the presence of an additional intron within the sequence encoding the BNP precursor. The identification of these introns suggests that the BNP gene structure differs from the atrial natriuretic peptide gene in the location of intron 2. BNP mRNA encodes a propeptide of 131 amino acids, including a signal peptide domain (25 amino acids) and a prohormone domain (106 amino acids). Like atrial natriuretic peptide, the bioactive BNP sequence is localized at the carboxyl terminus of the prohormone. Although the carboxyl-terminal peptide sequences of porcine atrial natriuretic peptide and BNP are well conserved, there is relatively little homology within their propeptide regions.

Amino Acid Sequence↗

PubMed1992

Hepatobiliary excretion of bacterial formyl-methionyl peptides in rat. Structure activity studies.

The bacterial chemotactic peptide formyl-met-leu-phe and its radioiodinated analog formyl-met-leu-[125I]tyr are rapidly excreted by the liver into bile following portal or systemic venous infusions in rats or after absorption from the gut lumen. To determine the molecular structural requirements for hepatobiliary excretion of formyl-methionyl peptides, structure-activity studies using portal venous infusions of 24 structural analogs of formyl-met-leu-tyr were performed in rats with biliary cannulae. Hepatic extraction of peptides was studied in vivo using external gamma counting after portal infusion. Efficient hepatobiliary excretion was not restricted to bioactive formyl peptides, but showed a broad specificity for different amino-acylated (formyl, acetyl, propionyl, carbobenzoxy) di- and tripeptides and no requirement for methionine in position one or for a free carboxy terminus. However, nonacylated peptides and an acyl-amino acid showed little excretion. Hepatic extraction of peptide was also related to N-acylation. Hepatic extraction and excretion of N-acyl peptides were also related to hydrophobicity. Thus, the presence of an N-acyl group is the key determinant of biliary excretion of inflammatory bacterial f-met peptides in the rat.

Animals↗

PubMed1990

FMRFamide-like peptides in the locust: distribution, partial characterization and bioactivity.

The quantitative distribution of FMRFamide-like peptides in the nervous system and in their putative target sites in the locust Schistocerca gregaria is described using radioimmunoassay techniques. The nature of the immunoreactive material has been characterized by high-pressure liquid chromatography. At least six peaks of FMRFamide-like immunoreactivity can be separated in extracts of locust nervous tissue. The relative proportions of these peaks vary from tissue to tissue, suggesting a differential expression of FMRFamide-like peptides in different parts of the locust nervous system. The bioactivity of the endogenous FMRFamide-like peptides has been assessed on the extensor tibiae neuromuscular preparation and on the locust heart. The results suggest that FMRFamide-like peptides in the locust function both as circulating neurohormones and as locally released neuromodulators or neurotransmitters.

Animals↗

PubMed1996

In vivo exposure to nitrogen dioxide (NO2) induces a decrease in calcitonin gene-related peptide (CGRP) and tachykinin immunoreactivity in guinea-pig peripheral airways.

The mammalian respiratory tract is densely innervated by sensory and autonomic fibres. Subsets of the nerves contain bioactive regulatory peptides, such as substance P, calcitonin gene-related peptide (CGRP), and neurokinins. The sensory nervous system responds to inhaled irritants, resulting in a release of neuropeptides and, thus, a decrease in the peptide immunoreactivity of the fibres. We examined the effects of inhaled nitrogen dioxide (NO2), a well-known indoor and outdoor air pollutant, on pulmonary sensory neuropeptides. Guinea-pigs were exposed for 4 h to 18 parts per million (ppm) NO2 or to air (n = 5 each). At the end of the exposure, they were killed with urethane and their lungs were fixed in 1% paraformaldehyde in phosphate-buffered saline. Cryostat sections were stained with antisera to an anatomical nerve marker, protein gene product (PGP) 9.5, and to CGRP and tachykinins, utilizing the avidin-biotinylated peroxidase method. In the noncartilaginous airways (diameter < 250 microns) of NO2-exposed animals, less tachykinin- and CGRP-immunoreactive nerve fibres were found compared with controls. No change was seen in the total nerve fibre distribution (PGP 9.5). It is concluded that the peptidergic nerves of guinea-pig peripheral airways are a sensitive indicator of exposure to nitrogen dioxide.

Administration, Inhalation↗

PubMed2003

Amino acids induce indicators of response to injury in glomerular mesangial cells.

High-protein diets exacerbate glomerular hyperfiltration and the progression of diabetic nephropathy. The purpose of this study was to determine whether amino acids also produce nonhemodynamic injury in the glomerulus. When rat mesangial cells were cultured with an amino acid mixture designed to replicate the composition in plasma after protein feeding, production of mRNA (Northern blot analysis) and/or protein (ELISA or Western blot analysis) for transforming growth factor-beta1 (TGF-beta1), fibronectin, thrombospondin-1 (TSP-1), and collagen IV were enhanced in a manner comparable to a culture with high glucose (30.5 mM). The bioactive portion of total TGF-beta (NRK assay) increased in response to amino acids. The TSP-1 antagonist LSKL peptide reduced bioactive TGF-beta and fibronectin, indicating the dependence of TGF-beta1 activation on TSP-1. DNA synthesis ([3H]thymidine incorporation), an index of cellular proliferation, increased in response to amino acids and was further enhanced by culture with increased levels of both amino acids and glucose. TGF-beta1 and matrix proteins increased when mesangial cells were cultured with excess l-arginine (2.08 mM) alone. Although l-arginine is the precursor of nitric oxide (NO), such responses to amino acids do not appear to be mediated through increased NO production. NO metabolites decreased in the media, and these responses to mixed amino acids or l-arginine were not prevented by NO synthase inhibition. In conclusion, amino acids induce indicators of response to injury in mesangial cells, even when hemodynamic stress is absent. In conditions associated with increased circulating amino acids, such as diabetes and/or a high-protein diet, direct cellular effects could contribute to glomerular injury.

Amino Acids↗

PubMed2005

Biochemical properties of peptides encrypted in bovine milk proteins.

Milk proteins are precursors of many different biologically active peptides. These peptides are inactive within the protein sequence, requiring enzymatic proteolysis for release of the bioactive fragment from the proteins precursor. It is evident that activated peptides originating from milk proteins should be taken into account as potential modulators of various regulatory processes in the body. Activated peptides are potential modulators of various regulatory processes in the living system: immuno-modulatory peptides stimulate the activities of cells of the immune system and several cytomodulatory peptides inhibit cancer cell growth, antimicrobial peptides kill sensitive microorganisms, angiotensin-I-converting enzyme (ACE)-inhibitory peptides exert an hypotensive effect, opioid peptides are opioid receptor ligands which can modulate absorption processes in the intestinal tract, mineral binding peptides may function as carriers for different minerals, especially calcium, antithrombotic peptides inhibit fibrinogen binding to a specific receptor region on the platelet surface and inhibit aggregation of platelets. Moreover, many milk-derived peptides reveal multifunctional properties, i.e. specific peptide sequences having two or more different biological activities have been reported. Bioactive peptides can interact with target sites (e.g. receptors, enzymes) at the luminal side of the intestinal tract, or they could be absorbed and reach any potential site of action in the system to elicit physiological effects. Bioactive peptides encrypted in bovine milk proteins can be produced on an industrial-scale and are claimed to be health enhancing components for functional foods, nutraceuticals and pharmaceutical preparations that are used to reduce risk of disease or to enhance certain physiological functions.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1986

Peptidergic modulation of a neuromuscular junction in Aplysia: bioactivity and immunocytochemistry.

Three endogenous peptides were assayed for bioactivity at an Aplysia neuromuscular junction. Evoked contractions were enhanced by Phe-Met-Arg-Phe-NH2 (FMRFamide) and suppressed by arginine vasotocin; small cardioactive peptide B (SCPB) also enhanced contractions at low concentrations, but caused suppression at higher doses. In accordance with their putative roles as neuromodulators, immunocytochemistry revealed FMRFamide-like and SCPB-like fibers on the muscle surface.

Animals↗

PubMed1994

Trefoil peptides promote epithelial migration through a transforming growth factor beta-independent pathway.

The trefoil peptides, a recently recognized family of protease-resistant peptides, expressed in a regional specific pattern throughout the normal gastrointestinal tract. Although these peptides have been hypothesized to act as growth factors, their functional properties are largely unknown. Addition of recombinant trefoil peptides human spasmolytic polypeptide (HSP), rat and human intestinal trefoil factor (RITF and HITF) to subconfluent nontransformed rat intestinal epithelial cell lines (IEC-6 and IEC-17), human colon cancer-derived cell lines (HT-29 and CaCO2) or nontransformed fibroblasts (NRK and BHK) had no significant effect on proliferation. However addition of the trefoil peptides to wounded monolayers of confluent IEC-6 cells in an in vitro model of epithelial restitution resulted in a 3-6-fold increase in the rate of epithelial migration into the wound. Stimulation of restitution by the trefoil peptide HSP was enhanced in a cooperative fashion by the addition of mucin glycoproteins purified from the colon or small intestine of either rat or man, achieving up to a 15-fold enhancement in restitution. No synergistic effect was observed by the addition of nonmucin glycoproteins. In contrast to cytokine stimulation of intestinal epithelial cell restitution which is mediated through enhanced TGF beta bioactivity, trefoil peptide, and trefoil peptide-mucin glycoprotein stimulation of restitution was not associated with alteration in concentrations of bioactive TGF-beta and was not affected by the presence of immunoneutralizing anti-TGF beta antiserum. Collectively, these findings suggest that the trefoil peptides which are secreted onto the lumenal surface of the gastrointestinal tract may act in conjunction with the mucin glycoprotein products of goblet cells to promote reestablishment of mucosal integrity after injury through mechanisms distinct from those which may act at the basolateral pole of the epithelium.

Animals↗

PubMed2006

Peptide aptamers as guides for small-molecule drug discovery.

Peptide aptamers are combinatorial protein reagents that bind to target proteins with a high specificity and a strong affinity. By so doing, they can modulate the function of their cognate targets. Because peptide aptamers introduce perturbations that are similar to those caused by therapeutic molecules, their use identifies and/or validates therapeutic targets with a higher confidence level than is typically provided by methods that act upon protein expression levels. The unbiased combinatorial nature of peptide aptamers enables them to 'decorate' numerous polymorphic protein surfaces, whose biological relevance can be inferred through characterization of the peptide aptamers. Bioactive aptamers that bind druggable surfaces can be used in displacement screening assays to identify small-molecule hits to the surfaces. The peptide aptamer technology has a positive impact on drug discovery by addressing major causes of failure and by offering a seamless, cost-effective process from target validation to hit identification.

Animals↗

PubMed1998

Gastric epithelial cells secrete a PDGF-like peptide, a potent mitogen for human gastric fibroblasts.

To investigate whether gastric epithelial cells secrete growth factors involved in stromal cell growth, we examined the effects of conditioned media obtained from gastric cancer cells on murine BALB/c 3T3 cells and primary cultured human gastric fibroblasts. Conditioned media from MKN-1 gastric cancer cells were applied to a heparin-affinity column. The fraction eluted from the column at 0.4 M NaCl stimulated DNA synthesis and phosphorylation of PDGF alpha-receptors on tyrosine in BALB/c 3T3 cells. The fraction-induced stimulation of DNA synthesis in gastric fibroblasts was more marked than in BALB/c 3T3 cells. However, the fraction failed to stimulate DNA synthesis in CHO-ER cells overexpressing EGF receptors and phosphorylation of PDGF beta-receptors on tyrosine in BALB/c 3T3 cells. Immunoblot analysis of the media confirmed that PDGF-AA-like peptides are released from gastric cancer cells, immortalized gastric epithelial cells, and primary cultured gastric epithelial cells. Anti-PDGF neutralizing antibodies produced only a partial inhibition of 0.4 M NaCl fraction-induced enhanced DNA synthesis. Thus, in addition to PDGF-AA peptide, other bioactive substance(s) are probably released from MKN-1 gastric cancer cells. Our results suggest that gastric epithelial cells secrete PDGF-AA-like peptides responsible for stromal cell growth through paracrine mechanisms.

3T3 Cells↗

PubMed2005

A putative bioactive conformation for the altered peptide ligand of myelin basic protein and inhibitor of experimental autoimmune encephalomyelitis [Arg91, Ala96] MBP87-99.

[Arg(91), Ala(96)] MBP(87-99) is an altered peptide ligand (APL) of myelin basic protein (MBP), shown to actively inhibit experimental autoimmune encephalomyelitis (EAE), which is studied as a model of multiple sclerosis (MS). The APL has been rationally designed by substituting two of the critical residues for recognition by the T-cell receptor. A conformational analysis of the APL has been sought using a combination of 2D NOESY nuclear magnetic resonance (NMR) experiments and detailed molecular dynamics (MD) calculations, in order to comprehend the stereoelectronic requirements for antagonistic activity, and to propose a putative bioactive conformation based on spatial proximities of the native peptide in the crystal structure. The proposed structure presents backbone similarity with the native peptide especially at the N-terminus, which is important for major histocompatibility complex (MHC) binding. Primary (Val(87), Phe(90)) and secondary (Asn(92), Ile(93), Thr(95)) MHC anchors occupy the same region in space, whereas T-cell receptor (TCR) contacts (His(88), Phe(89)) have different orientation between the two structures. A possible explanation, thus, of the antagonistic activity of the APL is that it binds to MHC, preventing the binding of myelin epitopes, but it fails to activate the TCR and hence to trigger the immunologic response. NMR experiments coupled with theoretical calculations are found to be in agreement with X-ray crystallography data and open an avenue for the design and synthesis of novel peptide restricted analogues as well as peptide mimetics that rises as an ultimate goal.

Amino Acid Sequence↗

PubMed1996

The immunodominant major histocompatibility complex class I-restricted antigen of a murine colon tumor derives from an endogenous retroviral gene product.

Tumors express peptide antigens capable of being recognized by tumor-specific cytotoxic T lymphocytes (CTL). Immunization of mice with a carcinogen-induced colorectal tumor, CT26, engineered to secrete granulocyte/macrophage colony-stimulating factor, routinely generated both short-term and long-term CTL lines that not only lysed the parental tumor in vitro, but also cured mice of established tumor following adoptive transfer in vivo. When either short-term or long-term CTL lines were used to screen peptides isolated from CT26, one reverse-phase high performance liquid chromatography peptide fraction consistently sensitized a surrogate target for specific lysis. The bioactivity remained localized within one fraction following multiple purification procedures, indicating that virtually all of the CT26-specific CTL recognized a single peptide. This result contrasts with other tumor systems, where multiple bioactive peptide fractions have been detected. The bioactive peptide was identified as a nonmutated nonamer derived from the envelope protein (gp70) of an endogenous ecotropic murine leukemia provirus. Adoptive transfer with CTL lines specific for this antigen demonstrated that this epitope represents a potent tumor rejection antigen. The selective expression of this antigen in multiple non-viral-induced tumors provides evidence for a unique class of shared immunodominant tumor associated antigens as targets for antitumor immunity.

Animals↗

PubMed2006

A root-knot nematode secretory peptide functions as a ligand for a plant transcription factor.

Parasitism genes expressed in the esophageal gland cells of root-knot nematodes encode proteins that are secreted into host root cells to transform the recipient cells into enlarged multinucleate feeding cells called giant-cells. Expression of a root-knot nematode parasitism gene which encodes a novel 13-amino-acid secretory peptide in plant tissues stimulated root growth. Two SCARECROW-like transcription factors of the GRAS protein family were identified as the putative targets for this bioactive nematode peptide in yeast two-hybrid analyses and confirmed by in vitro and in vivo coimmunoprecipitations. This discovery is the first demonstration of a direct interaction of a nematode-secreted parasitism peptide with a plant-regulatory protein, which may represent an early signaling event in the root-knot nematode-host interaction.

Amino Acid Sequence↗