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At least 289 records · Page 16Linked to original sources

PubMed1999

Sequence conservation of repeat 3 region of the gene coding for the 15 kDa polyprotein within human and simian Loa loa.

The human and simian strains of Loa loa microfilariae are morphologically identical even though their periodicities vary. When using primate models (Mandrillus sphinx) of human loaisis for vaccination trials, the absence of any ongoing simian L. loa infection must be demonstrated. Nested primers derived from a human strain of L. loa (targeted on the repeat 3 region of the gene encoding the 15 kDa polyprotein; 15r3) amplified at 366 bp sequence from simian L. loa genomic DNA and blood lysates from mandrills infected with simian L. loa. This nested-PCR assay has been tested on 12 amicrofilaremic (AMF) mandrills (without filarial microfilariae) and was positive in four mandrills. The nested-PCR product derived from simian L. loa genomic DNA and from three of four AMF mandrills has been sequenced. No difference was observed between the four sequences, which, in addition, were 99.18% identical to the 15r3 of human L. loa. Therefore, the 15r3 sequence is conserved within human and simian L. loa. These results suggest that the four PCR-positive mandrills without circulating microfilariae had occult simian L. loa infections. The study demonstrates the ability of a nested-PCR assay to identify animals naturally infected with simian L. loa.

Animals↗

PubMed2006

Characterization of the plant-specific BREVIS RADIX gene family reveals limited genetic redundancy despite high sequence conservation.

To date, the function of most genes in the Arabidopsis (Arabidopsis thaliana) genome is unknown. Here we present the first analysis of the novel, plant-specific BRX (BREVIS RADIX) gene family. BRX has been identified as a modulator of root growth through a naturally occurring loss-of-function allele. The biochemical function of BRX is enigmatic, however several domains in BRX are conserved in the proteins encoded by the related BRX-like (BRXL) genes. The similarity between Arabidopsis BRXL proteins within these domains ranges from 84% to 93%. Nevertheless, analysis of brx brx-like multiple mutants indicates that functional redundancy of BRXLs is limited. This results mainly from differences in protein activity, as demonstrated by assaying the propensity of constitutively expressed BRXL cDNAs to rescue the brx phenotype. Among the genes tested, only BRXL1 can replace BRX in this assay. Nevertheless, BRXL1 does not act redundantly with BRX in vivo, presumably because it is expressed at a much lower level than BRX. BRX and BRXL1 similarity is most pronounced in a characteristic tandem repeat domain, which we named BRX domain. One copy of this domain is also present in the PRAF (PH, RCC1, and FYVE)-like family proteins. The BRX domain mediates homotypic and heterotypic interactions within and between the BRX and PRAF protein families in yeast (Saccharomyces cerevisiae), and therefore likely represents a novel protein-protein interaction domain. The importance of this domain for BRX activity in planta is underscored by our finding that expression of the C-terminal fragment of BRX, comprising the two BRX domains, is largely sufficient to rescue the brx phenotype.

Alleles↗

PubMed2003

Detecting protein sequence conservation via metric embeddings.

MOTIVATION: Comparing two protein databases is a fundamental task in biosequence annotation. Given two databases, one must find all pairs of proteins that align with high score under a biologically meaningful substitution score matrix, such as a BLOSUM matrix (Henikoff and Henikoff, 1992). Distance-based approaches to this problem map each peptide in the database to a point in a metric space, such that peptides aligning with higher scores are mapped to closer points. Many techniques exist to discover close pairs of points in a metric space efficiently, but the challenge in applying this work to proteomic comparison is to find a distance mapping that accurately encodes all the distinctions among residue pairs made by a proteomic score matrix. Buhler (2002) proposed one such mapping but found that it led to a relatively inefficient algorithm for protein-protein comparison. RESULTS: This work proposes a new distance mapping for peptides under the BLOSUM matrices that permits more efficient similarity search. We first propose a new distance function on peptides derived from a given score matrix. We then show how to map peptides to bit vectors such that the distance between any two peptides is closely approximated by the Hamming distance (i.e. number of mismatches) between their corresponding bit vectors. We combine these two results with the LSH-ALL-PAIRS-SIM algorithm of Buhler (2002) to produce an improved distance-based algorithm for proteomic comparison. An initial implementation of the improved algorithm exhibits sensitivity within 5% of that of the original LSH-ALL-PAIRS-SIM, while running up to eight times faster.

Algorithms↗

PubMed1996

The 1.8 A resolution structure of hevamine, a plant chitinase/lysozyme, and analysis of the conserved sequence and structure motifs of glycosyl hydrolase family 18.

The three-dimensional structure of hevamine, a plant enzyme with chitinase and lysozyme activity, has been refined at 1.8 A resolution to an R-factor of 14.9% and a free R-factor of 19.6%. The final model consists of all 273 amino acid residues and 206 ordered water molecules. Two non-proline cis-peptides were identified, involving Phe32 and Trp255, both of which are implicated in substrate binding. Other glycosyl hydrolase family 18 proteins with known three-dimensional structure are bacterial chitinase A, endo-beta-N-acetylglucosaminidase F1, endo-beta-N-acetylglucosaminidase H, and the two plant proteins concanavalin B and narbonin, which have no known enzymatic activity. All these structures contain a (beta alpha)8 barrel fold, with the two family 18 consensus regions roughly corresponding to the third and fourth barrel strands. This confirms the grouping of these proteins into family 18, which was only based on weak and local sequence similarity. The substrate specificity of the enzymes is determined by the loops following the barrel strands that form the substrate binding site. All enzymes have an aspartic acid and a glutamic acid residue in positions identical with Asp 125 and the catalytic Glu127 of hevamine. The lack of chitinase activity of concanavalin B and narbonin can be explained by the absence of one of these carboxylate groups, and by differences in the loops that form the substrate-binding cleft in hevamine.

Amino Acid Sequence↗

PubMed1990

Complete sequence of the Drosophila nonmuscle myosin heavy-chain transcript: conserved sequences in the myosin tail and differential splicing in the 5' untranslated sequence.

We have sequenced a cDNA that encodes the nonmuscle myosin heavy chain from Drosophila melanogaster. An alternatively spliced exon at the 5' end generates two distinct heavy-chain transcripts: the longer transcripts inserts an additional start codon upstream of the primary translation start site and encodes a myosin heavy chain with a 45-residue extension at its amino terminus. The remainder of the coding sequence reveals extensive homology with other conventional myosins, especially metazoan nonmuscle and smooth muscle myosin isoforms. Comparisons among available myosin heavy-chain sequences establish that characteristic differences in sequence throughout the length of both the globular myosin head and extended rod-like tail readily distinguish nonmuscle and smooth muscle myosins from striated muscle isoforms and predict a basis for their functional diversity.

Amino Acid Sequence↗

PubMed2002

Bacillus anthracis pXO1 plasmid sequence conservation among closely related bacterial species.

The complete sequencing and annotation of the 181.7-kb Bacillus anthracis virulence plasmid pXO1 predicted 143 genes but could only assign putative functions to 45. Hybridization assays, PCR amplification, and DNA sequencing were used to determine whether pXO1 open reading frame (ORF) sequences were present in other bacilli and more distantly related bacterial genera. Eighteen Bacillus species isolates and four other bacterial species were tested for the presence of 106 pXO1 ORFs. Three ORFs were conserved in most of the bacteria tested. Many of the pXO1 ORFs were detected in closely related Bacillus species, and some were detected only in B. anthracis isolates. Three isolates, Bacillus cereus D-17, B. cereus 43881, and Bacillus thuringiensis 33679, contained sequences that were similar to more than one-half of the pXO1 ORF sequences examined. The majority of the DNA fragments that were amplified by PCR from these organisms had DNA sequences between 80 and 98% similar to that of pXO1. Pulsed-field gel electrophoresis revealed large potential plasmids present in both B. cereus 43881 (341 kb) and B. thuringiensis ATCC 33679 (327 kb) that hybridized with a DNA probe composed of six pXO1 ORFs.

Bacillus↗

PubMed1992

Are the conserved sequences in segment 1 of gelsolin important for binding actin?

The minimal region required for actin binding in the smallest of the three domains of gelsolin (termed Segment 1 or S1) was previously defined by deletion mutagenesis as residues 37-126. Further analysis of NH2-terminal deletions here redefines the minimal functional core as residues 41-126. Amino acid substitutions within this core further elucidate the nature of the interaction of segment 1 with actin. Of 26 point mutants analyzed, 14 reduced the affinity for actin. The charged residues His 119, Arg 120, Glu 121, and Gln 123 appear to be involved in direct interaction with actin. Substitutions of Leu 108, Leu 112, and Val 117 by polar groups all affect the structural stability of segment 1 and thereby reduce binding affinity. In addition replacement of Glu 126 by aspartic acid modifies the physical properties of segment 1 and weakens binding. We have further shown that changing charged residues within the highly conserved pentapeptide sequence LDDYL (residues 108-112) has no effect on actin binding. This sequence, found in a number of different actin binding proteins, does not therefore constitute part of the interaction site. Similarly, substitution of the two acidic residues by basic ones within the DESG motif of segment 1 (residues 96-99, but also found near the COOH terminus of actin) does not impair binding. These results show the dangers of predicting functional sites on the basis of conserved sequences.

Acanthamoeba↗

PubMed1994

Sequence conservation and correlation measures in protein structure prediction.

The rapid elucidation of protein sequences has allowed multiple sequence alignments to be calculated for a wide variety of proteins. Such alignments reveal positions that exhibit amino acid conservation--either of specific chemical groups in active and binding sites or of the more chemically inert hydrophobic residues that contribute to the protein core. The latter can provide constraints on the position of the protein chain and any local periodicity can suggest the type of secondary structure. Conservation measures, however, cannot provide specific pairwise packing information (each conserved hydrophobic position might pack against any other). However, if correlated changes between positions were observed then specific pairs of residue could be identified as interacting and therefore probably spatially adjacent. Most 'observations' of correlated changes have been anecdotal and of the few systematic studies that have been made, most have mistakenly incorporated a strong bias towards selecting conserved positions. When the conservation effect is separated (as best as possible) then little correlation signal remains to help identify adjacent positions.

Animals↗

PubMed1993

Cloning of the human and murine ROM1 genes: genomic organization and sequence conservation.

Rom-1 and peripherin are related membrane proteins of the photoreceptor outer segments. Both proteins are located at the rims of the photoreceptor disks, where they may act jointly in disk biogenesis. Mutations in the gene (RDS) encoding peripherin cause autosomal dominant retinitis pigmentosa, autosomal dominant punctata albescens and butterfly macular degeneration in man, and retinal degeneration slow in mice. To facilitate ROM1 mutation and linkage analysis in inherited retinal diseases, we cloned and characterized the human and murine ROM1 genes. In both species, the ROM1 coding region is contained within approximately 1.8 kb of genomic DNA and is interrupted by only two introns. The structures of the ROM1 and RDS genes are similar, with perfect conservation of the intron splice sites. Putative transcription regulatory regions of the ROM1 locus, 5' to an apparent transcription start site, were identified by cloning the mouse Rom-1 gene and comparing the sequence to the human homologue. Alignment of the human and murine rom-1 predicted protein sequences with the peripherin polypeptides of four species reveals a high degree of conservation (47% overall identity between the six proteins) in the central hydrophilic domain of the two family members. Despite this conservation of sequence, the predicted pI's of only this region of rom-1 and peripherin differ substantially, being 5.2 and 8.2, respectively. The charge difference in this region may mediate the non-covalent association of these two proteins in vivo. The conserved genomic structure and sequence of ROM1 and RDS indicates that these genes evolved from a common ancestor by duplication event.

Amino Acid Sequence↗

PubMed1994

Extensive DNA sequence conservation throughout the Mycobacterium tuberculosis complex.

The Mycobacterium tuberculosis complex includes the four species M. tuberculosis, M. bovis, M. africanum, and M. microti. We sequenced 13 M. tuberculosis complex strains in the 16S-to-23S rDNA internal transcribed spacer (ITS). The ITS has a high rate of nucleotide substitution. Previous reports found three nucleotide substitutions in the ITS between two M. tuberculosis complex strains. In contrast, we found the same ITS sequence in all 13 M. tuberculosis complex strains (including all four species and M. bovis BCG). This finding confirms the conservation of 16S rDNA sequence and the high DNA-DNA relatedness found in previous studies. By the usual criteria, the four species of the M. tuberculosis complex would be considered a single species. In a phylogenetic analysis based on the ITS sequence, the four species of the M. tuberculosis complex were distinct from nontuberculous mycobacteria. The ITS contains at least seven potential sites for oligonucleotide probes with specificity for the M. tuberculosis complex.

Base Sequence↗

PubMed1997

Remarkable sequence conservation of transcripts encoding amphibian and mammalian homologues of quaking, a KH domain RNA-binding protein.

Mutations in the mouse quaking locus can result in two different types of developmental phenotypes: (1) a deficiency of myelin in the central nervous system that is accompanied by a characteristic tremor, or (2) embryonic lethality around day 9 of gestation. A quaking candidate gene (qkI) that encodes a KH motif protein has recently been identified. We have isolated and characterized cDNAs encoding the Xenopus quaking homologue (Xqua) and also assembled an almost complete human quaking sequence from expressed sequence tags. Sequence comparisons show that the amphibian and mammalian quaking transcripts exhibit striking conservation, both within the coding region and, unexpectedly, in the 3' UTR. Two Xqua transcripts 5 kb and 5.5 kb in length are differentially expressed in the Xenopus embryo, with the 5 kb transcript being detected as early as the gastrula stage of development. Using an in vitro assay, we have demonstrated RNA-binding activity for quaking protein encoded by the 5 kb transcript. Overall, the high sequence conservation of quaking sequences suggests an important conserved function in vertebrate development, probably in the regulation of RNA metabolism.

Amino Acid Sequence↗

PubMed1997

Sequence conservation in the attachment glycoprotein and antigenic diversity among bovine respiratory syncytial virus isolates.

Partial nucleotide sequences were determined from the coding regions of the attachment glycoprotein (G) mRNAS of eight isolates of bovine respiratory syncytial virus (BRSV). The antigenic characteristics of 18 field and reference isolates were analyzed using the reactivity patterns of monoclonal antibodies (MAbs) directed against the human respiratory syncytial virus (HRSV) and BRSV G. fusion protein (F), nucleoprotein (N), and phosphoprotein (P), by radioimmunoprecipitation and immunofluorescence assays. The MAb reaction patterns demonstrated some random antigenic differences among the isolates, but for the most part were cross-reactive to the viral protein epitopes, especially on the F protein. Structural differences in the F and P proteins were observed among BRSV isolates; the P protein migrated at three different apparent molecular weights on PAGE gels. Antigenic and structural variation occurs among isolates, however, the structural differences in the P protein did not correlate with the antigenic differences among the F, N and P proteins. The G mRNA nucleotide sequence identities were high, ranging from 94.1 to 99.9%, and the predicted amino acid sequence identities ranged from 89.9 to 99.6%. Variance was due to substitution point mutations. The G protein ectodomains contained areas of sequence divergence flanking a highly conserved region, with four cysteine residues, which is analogous to the putative HRSV receptor binding domain. The high sequence and amino acid identities and random antigenic diversity among the isolates indicates that the BRSV isolates analyzed belong in a monophyletic group.

Amino Acid Sequence↗

PubMed1992

A potential gene target in HIV-1: rationale, selection of a conserved sequence, and determination of NMR distance and torsion angle constraints.

Recently, the capability for determining the high-resolution, sequence-dependent structure of oligonucleotides in solution via careful analysis of multidimensional NMR spectra and structure refinement procedures has been developed. Consequently, the rationale for selection of a genome sequence as a target for drug design based on the detailed three-dimensional structure of the target is presented. The concept is illustrated by the successful search for a highly conserved region of the HIV-1 genome's long terminal repeat which could serve as a molecular target. A compound which could selectively bind the target sequence could inhibit both RNA transcription from the integrated provirus and the reverse transcription process. Of 148 unique HIV-1 sequences examined, 147 exhibit a 21-base conserved sequence (nucleotides 70-90 in HIVHXB2R) in the R region of the long terminal repeat. The only exception, a minor constituent for one individual, has a change in the penultimate base. A 13 base pair duplex sequence, [d(AGCTTGCCTTGAG).d(CTCAAGGCAAGCT)], from this conserved region was selected and synthesized for NMR structure studies. Phase-sensitive proton two-dimensional nuclear Overhauser enhancement (2D NOE) and double-quantum-filtered correlation (2QF-COSY) spectra were obtained at 500 MHz for the DNA duplex. Exchangeable and nonexchangeable proton resonances were assigned. Quantitative assessments of the 2D NOE cross-peak intensities for different mixing times were carried out using conventional Fourier transform NMR and the maximum likelihood method (MLM). Distance constraints, along with upper and lower bounds, were obtained from the 2D NOE intensities using the iterative complete relaxation matrix algorithm MARDIGRAS. Distances entailing both exchangeable and nonexchangeable protons were determined: 7-11 experimental distance constraints per residue including interresidue and interstrand distances. Simulations of the scalar coupling effects manifest in 2QF-COSY cross-peaks by means of the program SPHINX/LINSHA were compared with experimental data to yield torsion angle constraints for the sugar rings. A single conformer was inadequate to describe any of the sugar puckers, but a rapid two-state equilibrium with one conformer strongly dominant (75-95%) provided a good fit of the 2QF-COSY cross-peaks. The sugar pucker of the major conformer exhibited significant variability for the various nucleotides but was roughly 2'-endo. Though derived independently and subject to different time-averaging effects, the 2QF-COSY and 2D NOE results are in accord.

Base Sequence↗

PubMed1999

The 1.7 A crystal structure of the apo form of the soluble quinoprotein glucose dehydrogenase from Acinetobacter calcoaceticus reveals a novel internal conserved sequence repeat.

The crystal structure of a dimeric apo form of the soluble quinoprotein glucose dehydrogenase (s-GDH) from Acinetobacter calcoaceticus has been solved by multiple isomorphous replacement followed by density modification, and was subsequently refined at 1. 72 A resolution to a final crystallographic R-factor of 16.5% and free R-factor of 20.8% [corrected]. The s-GDH monomer has a beta-propeller fold consisting of six four-stranded anti-parallel beta-sheets aligned around a pseudo 6-fold symmetry axis. The enzyme binds three calcium ions per monomer, two of which are located in the dimer interface. The third is bound in the putative active site, where it may bind and functionalize the pyrroloquinoline quinone (PQQ) cofactor. A data base search unexpectedly showed that four uncharacterized protein sequences are homologous to s-GDH with many residues in the putative active site absolutely conserved. This indicates that these homologs may have a similar structure and that they may catalyze similar PQQ-dependent reactions.A structure-based sequence alignment of the six four-stranded beta-sheets in s-GDH's beta-propeller fold shows an internally conserved sequence repeat that gives rise to two distinct conserved structural motifs. The first structural motif is found at the corner of the short beta-turn between the inner two beta-strands of the beta-sheets, where an Asp side-chain points back into the beta-sheet to form a hydrogen-bond with the OH/NH of a Tyr/Trp side-chain in the same beta-sheet. The second motif involves an Arg/Lys side-chain in the C beta-strand of one beta-sheet, which forms a bidentate salt-bridge with an Asp/Glu in the CD loop of the next beta-sheet. These intra and inter-beta-sheet hydrogen-bonds are likely to contribute to the stability of the s-GDH beta-propeller fold.

Acinetobacter calcoaceticus↗

PubMed2006

The boundary of macaque rDNA is constituted by low-copy sequences conserved during evolution.

In Macaca mulatta, the single rDNA array is flanked by a patchwork of sequences including subregions of human Yp11.2, 4q35.2, and 10p15.3. This composite DNA region is characterized by unique or low-copy sequences, resembling a potentially transcribed region. The analysis of Cercopithecus aethiops, Presbytis cristata, and Hylobates lar suggests that this complex sequence organization could be shared by Old World monkey and lesser ape species. After the lesser apes/great apes divergence, the unique or nonduplicated DNA region underwent amplification and spreading, preferentially marking the p arm of acrocentric chromosomes bearing the rDNA. The molecular analysis of human acrocentric chromosomes revealed some extent of remodeling of the rDNA boundary: near the human NOR, a large 4q35.2 duplication partially resembles that found in MMU; conversely, infrequently represented Yp11.2 sequences totally differed from those of the macaque, and 10p15.3 sequences were lacking. Thus, although evolutionary events modified the sequence organization of the MMU rDNA boundary, its overall sequence feature and the preferential location in vicinity to the NOR have been conserved.

Animals↗

PubMed1997

Mutagenesis of charged residues in a conserved sequence in the 2-kinase domain of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase.

Arg-136, Glu-137, Arg-138 and Arg-139 are conserved in all sequences of the 2-kinase domain of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase. Their role was studied by site-directed mutagenesis. All the mutations had little, if any, effect on fructose-2,6-bisphosphatase activity. Mutations of Arg-136 and Glu-137 into Ala caused only minor modifications of phosphofructo-2-kinase activity. In contrast, mutation of Arg138 into Ala increased 280-fold the Km for fructose 6-phosphate of phosphofructo-2-kinase. Mutation of Arg-139 into Ala resulted in decreases in phosphofructo-2-kinase Vmax/Km for MgATP and fructose 6-phosphate 600-fold and 5000-fold respectively. Mutation of Arg-139 into Lys and Gln increased the Km of phosphofructo-2-kinase for MgATP (20-fold and 25-fold respectively) and for fructose 6-phosphate (8-fold and 13-fold), and the IC50 for MgADP (30-fold and 50-fold) and for magnesium citrate (7-fold and 25-fold). However, these two mutations did not affect nucleotide binding, as measured by quenching of intrinsic fluorescence. The changes in kinetic properties induced by mutations could not be attributed to structural changes. It is proposed that Arg-138 is involved in fructose 6-phosphate binding and that Arg-139 is probably involved in the stabilization of the transition state and so participates in catalysis.

Adenosine Triphosphate↗

PubMed1994

Region of a conserved sequence motif in a class II tRNA synthetase needed for transfer of an activated amino acid to an RNA substrate.

The class II Escherichia coli alanine tRNA synthetase aminoacylates RNA miniduplexes, which reconstruct the acceptor end of alanine tRNA with the critical G3:U70 base pair. A benzophenone photoaffinity label attached adjacent to G3:U70 in a miniduplex substrate was previously cross-linked to a long enzyme peptide that begins at Gly161 between the class-defining motifs 2 and 3 [Musier-Forsyth, K., & Schimmel, P. (1994) Biochemistry 33, 773-779]. To identify side chains in this peptide that potentially contribute hydrogen bonding or catalytic determinants for the RNA-dependent step of the aminoacylation reaction, peptide functional side chains that are conserved among sequenced alanine enzymes (Asp, Asn, Arg, Glu, Gln, and Tyr) were individually replaced. Of the 21 mutant proteins so generated, one was identified that was not viable even though it accumulated in vivo. This Asp235-->Ala mutant enzyme is defective in the rate of transfer of the activated amino acid to the 3'-end of the RNA substrate. The conserved Asp235 is at the beginning of motif 3. By comparison with the crystal structure of the related class II yeast aspartate tRNA synthetase complexed with tRNA(Asp) (Cavarelli et al., 1993), we suggest that D235 is not in direct contact with acceptor helix base pairs such as G3:U70. Instead, we propose that D235 contributes to transfer-step interactions at the 3'-end of alanine tRNA. Because D235 in alanine tRNA synthetase is at the beginning of one of the conserved motifs that define class II tRNA synthetases, this region of the structure may in general be important for the transfer step.

Alanine-tRNA Ligase↗

PubMed1986

Sequence conservation around the 5' ends of the larval serum protein 1 genes of Drosophila melanogaster.

We have determined the nucleotide sequence at the 5' ends of the genes for the alpha, beta and gamma polypeptides of larval serum protein 1 (LSP1) of Drosophila melanogaster. In their upstream regions, the three genes share homology around the TATA boxes. There is also a homologous region of about 20 nucleotides at positions 200, 216 and 377 upstream from the alpha, beta and gamma genes, respectively. Another 18-nucleotide homology occurs between a sequence 111 nucleotides upstream from the alpha gene and 130 nucleotides upstream of the beta gene. This contains a seven-nucleotide match with a sequence 180 nucleotides upstream from the gamma gene. The sequences corresponding to the 5' non-translated regions of the RNA show two regions of strong homology: one being within the first 20 nucleotides at the very 5' end of the RNA, and the other being between nucleotides 27 and 52 of the three transcripts. The first AUG codon to precede a long open reading frame is found at nucleotides 89, 86 and 83 downstream from the 5' end of the alpha, beta and gamma RNAs, respectively. An extremely conserved nucleotide sequence with an exact homology of 66 nucleotides between the alpha and beta genes, and sharing 27 nucleotides with the gamma gene, is contained within this long open reading frame in the first exon. Conceptual translation of the long open reading frame shows that the hydrophobic nature of the first 20 amino acids of the three polypeptides has been conserved whereas the exact sequence has not. This suggests that the N termini contain signal sequences required for secretion of the protein into the haemolymph. The three genes have intervening sequences ranging from 65 to 68 nucleotides in length at comparable locations close to the 5' end of the genes.

Amino Acid Sequence↗