Esr,a second locus in the house mouse controlling esterase-5

Electrophoretic variation characterized by the presence (ES-5B⁺) or absence (ES-5B^–) of esterase-5B in the plasma of the house mouse has been observed. It is suggested that the expression of esterase-5B is controlled by an autosomal locus, Esr, linked to Ldr-1 on chromosome 6, in addition to the presumptive structural locus Es-5, which is located on chromosome 8. A gene order of Lyt-3-Esr-Ldr-1 was determined by two crosses.Supported by the Deutsche Forschungsgemeinschaft (SFB 46).This is communication No. 33 of a research program devoted to the investigation of cellular distribution and genetics of nonspecific esterases.     

Genetic characterization of esterase 28 (ES-28) of the house mouse

The genetics of esterase-28, the major esterase of cauda epididymidis of the house mouse, has been studied after separation by polyacrylamide gel electrophoresis and isoelectric focusing. Four phenotypes are distinguished. Segregation ofEs-28 in two backcross series indicated linkage to Es-1, Es-9, and Es-22. The Es-28 locus was placed into esterase cluster 1 on chromosome 8.This work was supported by the Deutsche Forschungsgemeinschaft.This is communication No. 69 of a research program devoted to the cellular distribution, genetics, and regulation of nonspecific esterases.     

Genetic variation and biochemical properties of esterase-18 (ES-18) in the laboratory rat (Rattus norvegicus): A new locus of esterase cluster 2 in linkage group V

A new liver-specific rat carboxylesterase isozyme (EC 3.1.1.1) designated esterase-18 (ES-18) is described. Genetic variation of ES-18 was examined in 93 inbred strains and substrains and a structural locusEs-18 was suggested, coding for either the presence (Es-18 ^a) or the absence (Es-18 ^b) of the isozyme. Linkage studies involving two backcross series revealed thatEs-18 resides in cluster 2 of LGV. No recombination betweenEs-18 and other cluster 2 loci was found in 19 lines of two RI strain sets or in the backcross series.R. K. was supported by the Sonderforschungsbereich 146 (Versuchstierforschung). O.D. was supported by the Deutsche Forschungsgemeinschaft (De 315/2). This is communication No. 65 of a research program devoted to the cellular distribution, regulation, and genetics of nonspecific esterases.     

Serine esterases: structural conservation during animal evolution and variability in enzymic properties in the genus Drosophila

Both general esterases and acetylcholinesterases have been shown to be members of a homologous superfamily of serine esterases. A comparison of N-terminal sequences demonstrates that esterase-4 and-5 from Drosophila mojavensis belong to this family as well, with esterase-6 and esterase-P from D. melanogaster being the closest relatives. In order to investigate the presence of immunologically related esterases in other Drosophila species, crude larval extracts from five species were applied to two immunoaffinity columns with antibodies directed against esterase-4 and esterase-5 from D. mojavensis. The substrate preference for either 1- or 2-naphthyl acetate was determined. Both esterase-4 and esterase-5 from D. mojavensis are normally specific for 2-naphthyl esters, but at least three of the cross-reacting esterases from the other species have a preference for 1-naphthyl esters. This difference in substrate preference is another example of the variability observed with Drosophila esterases.     

Esterases of Mus musculus: Substrate and inhibition characteristics,new isozymes,and homologies with man

A wide range of fluorogenic and naphthol esters has been tested as substrates for mouse esterases. New esterases have been identified in liver and kidney extracts with palmityl, oleyl, and elaidyl esters. From substrate, inhibition, and molecular weight studies, three homologies between human and mouse esterases are suggested. A new allele at Es-6 is also described.This work was supported by the Medical Research Council.     

Polymorphism of esterase-10 in Mus musculus

An esterase, esterase-10, in the house mouse, Mus musculus, is specific for esters of 4-methylumbelliferone and exhibits a polymorphism detectable by electrophoresis. Fifteen inbred strains and two outbred strains have been examined for this polymorphism, and two phenotypes, ES-10A and ES-10B, have been observed. Each phenotype manifests itself as a single band of enzyme activity, but under the electrophoretic conditions used the ES-10A phenotype has less anodal electrophoretic mobility than the ES-10B phenotype. In F₁ hybrids (C3H/He/Lac×C57BL/Gr) a third phenotype was observed, ES-10AB, consisting of three bands of enzyme activity, two of which correspond to the parental forms and the third with intermediate mobility. The triple-band pattern in the F₁ hybrids indicates that esterase-10 is a dimeric enzyme protein.This work was supported by the Medical Research Council.     

Organ specific expression of esterase-6 in the house mouse,Mus musculus

Summary Esterase-6 in fresh homogenates of heart muscle and testis of the house mouse shows a two band (C allele) or three band (A allele) pattern in disc electrophoresis. These primary bands generated a series of secondary bands upon lowering the pH of the homogenates, and the secondary pattern, possibly resulting from partial proteolysis, was seen in varying degrees in fresh homogenates from a range of organs. Interrelationships between the primary and secondary bands were demonstrated by isoelectric focusing. The esterase-6 content of twenty different organ homogenates was estimated from electrophoretic gels, and a high level of this enzyme was observed in those organs most actively involved in fat metabolism. The possible participation of esterase-6 in fatty acid utilization is discussed. Similarities between esterase-6 of the house mouse and esterase-4 of the rat were demonstrated, further strengthening the view that these enzymes are homologous.Supported by the Deutsche Forschungsgemeinschaft (SFB 46)This is communication no 36 of a research program devoted to the cellular distribution, genetics, and regulation of non-specific esterases     

Esterase-29 (ES-29): Biochemical characterization and control by two independent gene loci of a testosterone-dependent mouse serum esterase

Biochemistry and genetics of a testosterone-dependent murine serum esterase designated esterase-29 (ES-29) are described. The enzyme was identified after disc electrophoresis and subsequent staining for esterase using -naphthyl acetate as the substrate. It was inhibited by bis-p-nitrophenyl phosphate and was resistant top-chlorophenylsulphonate and hence was classified as carboxylesterase EC 3.1.1.1. The molecular mass was estimated to be about 130 kDa. It was shown that ES-29 is under the control of two independent genes. The first, termed Es-29, is suggested to be a structural locus, linked to the cluster-2 esterase loci on chromosome 8. Three alleles atEs-29, Es-29 ^a, Es-29^b, andEs-29 ^care distinguished, which determine absence (SEG/1), strong activity (BALB/cJ), and low activity (MOLH/Fre), respectively. The second locus, termedMse-1 (serum esterase modifying factor), was found to be closely linked toPre-2 on chromosome 12 and is suggested to be a modifying or regulatory gene. Two alleles were distinguished,Mse-1 ^a(BALB/cJ) andMse-1 ^m(MOL3/JA, CasBgr), which determine whether ES-29 appears as a single band or a double band, respectively.Mse-1 ^mis dominant toMse-1 ^a.This work was supported by the Deutsche Forschungsgemeinschaft. This is communication No. 70 of a research program devoted to the cellular distribution, genetics, and regulation of nonspecific esterases.     

Purine nucleoside phosphorylase (Np) in the mouse: Linkage relationship of Np-2 to esterase-10 (Es-10) and Np-1 on chromosome 14

An improved method for detecting four Np-1 (purine nucleoside phosphorylase) alleles in mouse erythrocytes by cellulose acetate electrophoresis is described. The previous linkage of Np-1 and Es-10 (esterase-10) was confirmed, with a map distance of 13.0±2.6 cM. Np-2 was detected by either specific activity assay or starch gel electrophoresis and shown to be linked to Es-10, 15.9 ± 3.1 cM, on chromosome 14. No recombinants between Np-1 and Np-2 were observed in 52 offspring, indicating either that these loci are either closely associated or that Np-2 represents simply a property of existing allelic products of the Np-1 locus.This research was supported by Medical Research Council of Canada grants to F.G.B. and F.F.S.     

Biochemical genetics of Es-14 (formerly Es-Si) and a new esterase variation,Es-15, of the laboratory rat (Rattus norvegicus): Biochemistry,tissue expression,and linkage to Es-1 in linkage group V

The segregation of rat esterases controlled by loci residing in linkage group V (LGV) has been studied in two backcross series, (LEW/Han × BN/Han)F₁ × LEW/Han and (LEW/Han × LE/Han)F₁ × LEW/Han. Es-14 (formerly Es-Si) was shown to be closely linked to Es-1. A new esterase locus, Es-15, was described which codes for a liver isozyme. The distribution pattern of three alleles at the Es-15 locus is presented for 52 independent inbred strains. Close linkage of Es-15 to Es-14 and to Es-1 was established, proposing the following gene order: [Es-2, Es-10]—[ES-1, ES-14, ES-15]. The esterase loci on LGV are thus separated into two gene clusters, cluster 1 and cluster 2. These conclusions are supported by the strain distribution patterns of the two RI strain series, LXB and DXE.Otto von Deimling was supported by the Deutsche Forschungsgemeinschaft (De 315/2-1, communication No. 56).     

Esterase-30 (ES-30) of the house mouse: Biochemical characterization and genetics of a new carboxylesterase isozyme linked to cluster-2 loci on chromosome 8

A new carboxylesterase isozyme (EC 3.1.1.1), designated ES-30, is described in mouse liver. Two phenotypes were distinguished, ES-30A, a possible null type, was found in SPE/Pas and in other lines derived fromMus spretus, and ES-30B was found in BALB/cJ and other laboratory inbred strains. ES-30B is characterized by a distinct electrophoretic band when stained using 5-bromoindoxyl acetate as the substrate. After isolation and purification from other esterases by ion-exchange chromatography and molecular sieving, the molecular mass was estimated by two independent methods to be 62 and 64 kDa, respectively. The activity of ES-30B is higher in adult males than in females and can be stimulatedin vivo by testosterone. The distribution of phenotypes on the progeny of a backcross series suggests a separate locus,Es-30, with the allele a for absence andb for presence of the isozyme. LocusEs-30 is shown to be closely linked toEs-2 and toEs-7 of cluster-2 on chromosome 8. The gene orderEs-9—Got-2—(Es-2, Es-7, Es-30) is suggested. This work was supported by the Deutsche Forschungsgemeinschaft. This is communication No. 72 of a research program devoted to the cellular distribution, genetics, and regulation of nonspecific esterases.     

Genetics of esterases in Drosophila of the virilis group. I. Characteristics of esterase patterns in D. virilis,D. texana,D. littoralis,and their hybrids

Starch and polyacrylamide gel electrophoreses have detected six esterase fractions in Drosophila of the virilis group. These esterases have been characterized in detail using a series of substrates and inhibitors and also thermal treatment. Differences in esterase patterns have been found between D. virilis, D. texana, and D. litoralis as well as between D. virilis stocks. An interstock polymorphism for different esterase patterns has been established with respect to the electrophoretic mobilities of a number of esterase fractions. In rare instances, it has been observed within some D. virilis stocks, too. There is specificity in organ distribution of esterase fractions in Drosophila. Monogenic control of the electrophoretic mobilities of esterase-2 and esterase-4 has been demonstrated in D. virilis, and a dimer structure has been found in esterase-2. Genes controlling esterase-2 and esterase-4 are located on the second chromosome (209.3 for esterase-2 and 192.0 for esterase-4). In interstock and interspecific hybrids, esterases usually manifest codominance. In interstock hybrids, esterase-2 forms a hybrid band not observed in interspecific hybrids. In third instar larvae of interspecific hybrids, differential expression of certain esterase isozymes has been noted. These observations are in agreement with data from histochemical studies of organs of different hybrids.     

Identity of esterase-22 and egasyn,the protein which complexes with microsomal β-glucuronidase

Recent experiments have demonstrated that egasyn not only sequesters -glucuronidase in microsomes by forming high molecular weight complexes with -glucuronidase, but also has carboxyl esterase activity. We have found several new phenotypes of egasyn-esterase after electrophoresis and isoelectric focusing of liver homogenates and purified egasyn of inbred and wild mouse strains. Several phenotypes corresponded in relative mobility and relative isoelectric point among inbred strains to that recently reported for esterase-22 by Eisenhardt and von Deimling [(1982). Comp. Biochem. Physiol. 73B:719]. This genetic evidence, plus a wide variety of comparative biochemical and physiological data, indicates that egasyn is identical to esterase-22. Both parental types of egasyn isozymes are expressed in heterozygous F₁ progeny, suggesting that alterations in the egasyn structural gene are responsible for the altered isoelectric points. Also, egasyn is a monomer since no new esterase bands appear in F₁ progeny. The variants in isoelectric point of egasyn map at or near the egasyn (Eg) gene within the esterases of cluster 1 near Es-9 on chromosome 8.This work was supported by Grant GM-33559 from the National Institutes of Health.     

A fourth allele in the plasma esterase-1 (Es-1) system of the domestic fowl

Plasma samples of fowl were analysed by horizontal polyacrylamide gel electrophoresis (pH 9.0). Evidence was presented for the subdivision of an earlier reported esterase-1 allele (Es-1A) into two alleles designated Es-1A1 and Es-1A2. Family data were consistent with the hypothesis that the Es-1 phenotypes were controlled by four codominant, autosomal alleles Es-1C, Es-1A1, Es-1A2 and Es-1B). The White Leghorn samples showed high frequency of Es-1A1 (about 0.7) and also had considerable frequency of Es-1A2 (0.2) and of Es-1B (0.1). The three meat-type breeds studied (White Plymouth Rock, Rhode Island Red and New Hampshire) showed a very high frequency of Es-1B (0.8-1.0).     

Es-6, a further polymorphic esterase in the rat

A further polymorphic rat esterase with broad tissue expression and restricted substrate specificity is described and tentatively called Es-6. Inbred rat strains have either fixed allele Es-6^F or fixed allele Es-6^S. Es-6 is not linked to the established esterase cluster consisting of the eight esterase loci Es-1, Es-2, Es-3M, Es-4M, Es-4W, Es-5 (=Es-3W), Es-7, and Es-8 in LG V of the rat or to RT1, Gc, c, a, and h. Esterases with apparently identical biochemical and genetical characteristics are Es-17 of the mouse and Es-A4 of humans.Supported by the Deutsche Forschungsgemeinschaft (Be 352/13 and Gu 105).     

An episode of accelerated amino acid change in Drosophila esterase-6 associated with a change in physiological function

In most lineages of the subgenus Sophophora esterase-6 is a homodimeric haemolymph protein. In the melanogaster subgroup of species it has become a monomer which is mainly expressed in the male sperm ejaculatory duct. Our analyses of esterase-6 sequences from three melanogaster subgroup species and two close relatives reveal a brief period of accelerated amino acid sequence change during the transition between the ancestral and derived states. In this period of 2–6Myr the ratio of replacement to silent site substitutions (0.51) is about three times higher than the values in other lineages of the phylogeny. There are about 50 more replacements in this period than would be predicted from the ratios of replacement to silent site substitutions found elsewhere in the phylogeny. Modelling on the known structure of a related acetylcholinesterase suggests that an unusually high proportion of the replacements in the transitional branch are non-conservative changes on the protein surface. Up to half the accelerated replacement rate can be accounted for by clusters of changes to the face of the molecule containing the opening of the active site gorge. This includes changes in and around regions homologous to peripheral substrate binding sites in acetylcholinesterase. There are also three changes in glycosylation status. One region predicted to lie on the protein surface which becomes markedly more hydrophilic is proposed to be the ancestral dimerisation site that is lost in the transitional branch. This revised version was published online in July 2006 with corrections to the Cover Date.     

Esterase-17 (ES-17): Characterization and genetic location on chromosome 9 of a bis-p-nitrophenyl phosphate-resistant esterase of the house mouse (Mus musculus)

Genetic variation of a new codominantly inherited esterase, designated ES-17, has been discovered in the house mouse using isoelectric focusing in polyacrylamide gels. The ES-17 A phenotype (three bands; isoelectric points, betweenpH 5.55 andpH 5.90) was found in C57 BL/10Sn. LP/J possessed the Es-17B phenotype (three bands; isoelectric points,pH 5.05–5.55). ES-17 was present in all tissues examined, except for hemolysate and serum, and was most clearly expressed in the small intestine. Because of its reaction toward various substrates and inhibitors, ES-17 has tentatively been classified as acetyl esterase (EC 3.1.1.6). ES-17 was shown to be controlled by the structural locusEs-17, located on chromosome 9. From test-cross data, a gene order ofEs-17-8.7±2.5 map units-Mpi-1-10.2±2.7 map units-Mod-1 was established. This work was supported by the Deutsche Forschungsgemeinschaft (SFB 46). This is communication No. 35 of a research program devoted to the cellular distribution and genetics of nonspecific esterases.     

Esterase-7, a common constituent of numerous mouse tissues.

1. Electrophoretic and staining techniques for the relatively specific demonstration of esterase-7 in mouse tissues are described. Esterase-7 was found to be a common constituent of most mouse tissues. 2. The electrophoretic polymorphisms determined by three alleles a, b and c were studied in nine mouse strains. 3. The banding pattern of esterase-7 is being described and the isoelectric points of the allelic bands are being estimated. 4. Recombination studies on a further 129 animals confirmed that the Es-7 locus is tightly linked to Es-2 and Es-11. 5. Esterase-7 precipitates with antiesterase-2 from the rabbit. 6. It differs from esterase-2 by its individual substrate preference and by its susceptibility to inhibition by acylating agents.     

Esterase. XXI. Es-9, a possibly new polymorphic esterase in Mus musculus genetically linked to Es-2

A so far undescribed gene controlling zone III esterases has been detected by means of disc gel electrophoresis of kidney homogenates from the two inbred mice strains NMRI and SK/Cam. The gene is tentatively designated Es-9, and the two codominant alleles are designated Es-9a and Es-9b. Es-9 esterases are present in many tissues, but, unlike the other zone III esterase (controlled by Es-5), are not found in the serum. Close linkage with the Es-2 gene leads us to map the Es-9 gene on chromosome 8.     

Biochemistry and genetics of esterase-20 (ES-20), a second trimeric carboxylesterase of the house mouse (mus musculus). II. A unique recombination reveals ES-20 as a hybrid enzyme

A unique recombination is described between (Es-1, Es-6) and (Es-9, Es-22) within gene cluster 1 of the esterase gene region on chromosome 8 of the house mouse. This recombination established the gene order Es-1--Es-6--(Es-9, Es-22)--Got-2. A further 73 recombinations, from a total of 911 backcrosses, had taken place between cluster 1 and cluster 2. A distance between the clusters of 8.01 +/- 0.90% was calculated; the genes within the clusters appeared more tightly linked than previously assumed. ES-20 behaved anomalously following the recombination within cluster 1: homozygous descendants of the recombinant expressed a new form of ES-20. In vitro incubation of purified ES-6A3 and ES-9A generated ES-20A, revealing this esterase to be a hybrid of different cluster 1 gene products, Es-9 and possibly Es-6. This result satisfactorily accounted for the genetic finding, as well as a range of biochemical properties of ES-20.