Polymorphism of alanine aminotransferase (E.C.2.7.6.1): Common and rare alleles

Summary Gene frequencies of common and rare GPT alleles derived from an investigation of 1139 unrelated, healthy individuals from southwestern Germany are given. GPT typing was performed by means of horizontal starch gel electrophoresis in a Tris-histidinexHCl buffer system. In addition, a new electrophoretic variant, GPT ⁹, is described.The frequencies of the GPT alleles observed were calculated as: GPT ¹ 0.4987; GPT ², 0.4686; GPT ^1M, 0.022; GPT ⁰, 0.005; GPT ³, 0.0022; GPT ⁴, 0.0025; GPT ⁸, 0.0005; GPT ⁹, 0.0005.     

Physiological effects of an allozyme polymorphism: Glutamate-pyruvate transaminase and response to hyperosmotic stress in the copepod Tigriopus californicus

In order to regulate cell volume during hyperosmotic stress, the intertidal copepod Tigriopus californicus, like other aquatic crustaceans, rapidly accumulates high levels of intracellular alanine, proline, and glycine. Glutamate-pyruvate transaminase (GPT; EC 2.6.1.2), which catalyzes the final step of alanine synthesis, is genetically polymorphic in T. californicus populations at Santa Cruz, California. Spectrophotometric studies of homogenates derived from a homozygous isofemale line of each of the two common GPT alleles indicated that the GPT^F allozyme has a significantly higher specific activity than the GPT^S allozyme. Under conditions of hyperosmotic stress, individual adult copepods of GPT^F and GPT^F/S genotypes accumulated alanine, but not glycine or proline, more rapidly than GPT^S homozygotes. When young larvae were subjected to the same hyperosmotic conditions, GPT^S larvae suffered a significantly higher mortality than GPT^F or GPT^F/S larvae. These results suggest that the biochemical differences among GPT allozymes result in specific physiological variation among GPT genotypes and that this physiological variation is manifested in differential genotypic survivorships under some naturally occurring environmental conditions.This work was supported in part by a grant from the Lerner Fund for Marine Research of the American Museum of Natural History, an NIH Training Grant in Integrative Biology, and NIH Grants GM 28016 and GM 10452.     

Polymorphismus der menschlichen Erythrocyten-Glutamat-Pyruvat-Transminase

Zusammenfassung Bei einer Stichprobe nichtverwandter Personen aus der Bevölkerung von Berlin (West) wurden folgende GPT-Frequenzen gefunden: GPT¹ 0,512, GPT² 0,484, GPT³ 0,004. Dieses Ergebnis stimmt mit anderen Untersuchungen aus Deutschland gut überein.

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Polymorphism of the human red cell glutamate-pyruvate transaminase

Summary In a random population sample in Berlin (West) the following GPT-Frequencies were found: GPT¹ 0.512, GPT² 0.484, GPT³ 0.004. This is consistent with other results obtained in German populations.

     

Untersuchungen zum GPT-System unter besonderer Berücksichtigung des stummen Allels GPT0

Zusammenfassung Von 4208 nichtverwandten freiwilligen Blutspendern aus Hessen wurden die GPT-Phänotypen bestimmt und folgende Genfrequenzen errechnet: GPT¹=0,5228; GPT²=0,4737; GPT³=0,0035.Bei der Untersuchung von 108 Familien mit 159 Kindern ergab sich keine Abweichung von der Erbregel.Eine im Rahmen der Familienuntersuchungen zunächst als entgegengesetzte Homozygotie von Mutter und Kind imponierende Diskrepanz konnte durch den Nachweis eines stummen Gens (GPT⁰) abgeklärt werden.Die derzeit vorliegenden Ergebnisse über den GPT-Polymorphismus werden im Hinblick auf dessen Einführung in die forensische Vaterschaftsbegutachtung diskutiert.

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Studies on the GPT system, with special reference to the silent gene GPT⁰

Summary The GPT phenotypes were determined in 4208 non-related voluntary blood donors in Hessen. The following gene frequencies were calculated: GPT¹=0.5228; GPT²=0.4737; GPT³=0.0035.In a study of 108 families with 159 children no exceptions to the laws of inheritance were observed.In this family study one discrepancy, at first assumed to be a mother/child incompatibility (opposite homozygosity) proved to be due to a silent gene (amorph), GPT⁰.The results published on GPT polymorphism hitherto are discussed, with special reference to its implications for the assessment of paternity in forensic medicine.

     

Red cell glutamic-pyruvic transaminase gene frequencies in the region of the Po delta (Ferrara,Northern Italy)

Summary The red cell glutamic-pyruvic transaminase phenotype has been determined in 294 individuals from the region of the Po delta (Ferrara, Northern Italy). No correlation with past malarial morbidity has been detected. The gene frequencies found in this survey are similar to those reported for other Caucasian populations. One GPT ³ GPT ¹ individual has been found.Supported by a grant of the Consiglio Nazionale delle Ricerche (CNR).     

Population genetics of soluble glutamic-pyruvic-transaminase in North Germans (Lübeck)

Summary The soluble glutamic-pyruvate-transaminase activity in 103 mother-child combinations and 374 randomly selected individuals from a North German population was examined. The frequency of GPT¹ was found to be slightly higher than that of GPT², but this is in accordance with the various other German population groups. Investigation of mother-child combinations supports the assumption that GPT¹ and GPT² are dimers, i.e. each being composed of two identical subunits.

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Zusammenfassung Es wurde die Aktivität der löslichen Glutamat-Pyruvat-Transaminase bei 103 Mutter-Kind-Kombinationen und 374 auslesefrei gewonnenen Individuen einer norddeutschen Bevölkerung untersucht. Die Häufigkeit von GPT¹ ist etwas größer als die von GPT²; das stimmt mit den übrigen bisher untersuchten deutschen Bevölkerungsstichproben überein. Die Mutter-Kind-Kombinationen unterstützen die Auffassung, GPT¹ und GPT² seien Dimere, d. h. jeweils aus zwei identischen Untereinheiten zusammengesetzt.

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This study was carried out in 1972/73 during the author's tenure at the Medizinische Hochschule in Lübeck, West Germany.     

Zum Polymorphismus der Glutamat-Pyruvat-Transaminase (GPT) menschlicher Erythrocyten in Westdeutschland

Zusammenfassung Die erythrocytären Isoenzyme der Glutamat-Pyruvat-Transaminase von 1148 zufällig ausgewählten Deutschen aus dem Kölner Raum wurden mittels horizontaler Stärkegelelektrophorese bestimmt. Bei 751 Proben waren die Banden nicht ablesbar, was auf Überalterung der Blutproben und den damit verbundenen Aktivitätsverlust der GPT zurückgeführt wird. Bei 397 Hämolysaten waren die Banden eindeutig ablesbar. Für Gpt ¹ wurde als Genfrequenz 0,5479, für Gpt ² 0,4521 ermittelt, seltene Varianten wurden nicht beobachtet.

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Polymorphism of human red cell glutamic-pyruvic-transaminase (GPT) in Western Germany

Summary Red cell glutamic-pyruvic-transaminase was established by horizontal starchgel-electrophoresis. 1148 Germans from the Cologne area were examined, but only in 397 cases the results were clearly interpretable. This fact was atributed to a decrease of GPT-activity in aged blood samples. No rare variants were detected. The following gene-frequencies were found: GPT¹=0.5479, GPT²=0.4521.

     

Chromosomal and regional localization of the loci for IGKC,IGGC, ALDB,HOXB, GPT,and PRNP in the American mink (Mustela vison): comparisons with human and mouse

Chromosomal localization of the genes for gamma- and kappa-immunoglobulins (IGGC and IGKC, respectively), aldolase B (ALDB), prion protein (PRNP), homeo box B (HOXB), and glutamate pyruvate transaminase (GPT) were determined with the use of mink-rodent hybrid cells. Analysis of segregation of the mink markers and chromosomes in these hybrid cells allowed us to assign the gene for HOXE to Chromosome (Chr) 8, IGGC to Chr 10, PRNP and IGKC to Chr 11, ALDB to Chr 12, and GPT to Chr 14 in mink. Furthermore, using a set of mink-mouse hybrid cells carrying fragments of mink Chr 8 of different sizes, we assigned the gene for HOXB to the pter-p26 region of the short arm of Chr 8. Comparative mapping of the genes of mink, human, and mouse, as well as other mammalian species, demonstrated that the mink genes HOXB, PRNP, ALDB, and IGGC are members of a conserved region shared by many mammalian species in common; the IGKC gene is a member of a conserved region common to carnivores and primates, not rodents; the GPT gene is a member of a syntenic gene group probably unique to the Mustelidae family or carnivores.     

Development of a Series of Gateway Binary Vectors Possessing a Tunicamycin Resistance Gene as a Marker for the Transformation of Arabidopsis thaliana

We made two series of Gateway binary vectors, pGWBs and R4pGWBs, possessing a UDP-N-acetylglucosamine: dolichol phosphate N-acetylglucosamine-1-P transferase (GPT) gene driven by the nopaline synthase promoter (Pnos) as a tunicamycin resistance marker for the transformation of Arabidopsis thaliana. The reporters and tags employed in this system are sGFP, GUS, LUC, EYFP, ECFP, G3GFP, mRFP, TagRFP, 6xHis, FLAG, 3xHA, 4xMyc, 10xMyc, GST, T7, and TAP. Selection of transformants was successful on plates containing 0.15 mg/L of tunicamycin. These vectors were compatible with existing pGWB and R4pGWB vectors for kanamycin, hygromycin B, and BASTA^® selection, and are useful new tools for making transgenic Arabidopsis.     

Population genetics of soluble glutamic-pyruvic transaminase (EC:2.6.1.2): Gene frequencies in Southwestern Germany

Summary In a population sample from Southwestern Germany GPT-phenotypes have been determined. The allele GPT¹ is more frequent in this sample than in the USA.Supported by the Deutsche Forschungsgemeinschaft.     

The anaerobic fungusPiromyces sp. strain E2: nitrogen requirement and enzymes involved in primary nitrogen metabolism

The anaerobic fungusPiromyces sp. strain E2 appeared restricted in nitrogen utilization. Growth was only supported by ammonium as source of nitrogen. Glutamine also resulted in growth, but this was due to release of ammonia rather than to uptake and utilization of the amino acid. The fungus was not able to grow on other amino acids, albumin, urea, allantoin, or nitrate. Assimilation of ammonium is very likely to be mediated by NADP-linked glutamate dehydrogenase (NADP-GDH) and glutamine synthetase (GS). One transaminating activity, glutamate-oxaloacetate transaminase (GOT), was demonstrated. Glutamate synthase (GOGAT), NAD-dependent glutamate dehydrogenase (NAD-GDH), and the transaminating activity glutamate-pyruvate transaminase (GPT) were not detected in cell-free extracts ofPiromyces sp. strain E2. Specific enzyme activities of both NADP-GDH and GS increased four-to sixfold under nitrogen-limiting conditions.Abbreviations GDH Glutamate dehydrogenase - GOGAT Glutamate synthase - GOT Glutamate-oxaloacetate transaminase - GPT Glutamate-pyruvate transaminase - GS Glutamine synthetase     

Genetic study in Greek Sarakatsans. I. Blood groups and enzyme polymorphisms

A random sample from the endogamic population of Greek Sarakatsans has been studied for eight blood groups, eleven enzymic genetic systems and haemoglobin variants. The allelic frequencies of the polymorphic loci have been compared with those of other samples from the Greek mainland and other European populations. The Sarakatsans tend to resemble their neighbours. The comparison with European populations indicates that the Sarakatsans have gene frequencies similar to other Mediterranean and European populations. However, the monomorphism of the Kell system, the low frequency of the ACP^*B, AK^*1 and GLO^*1 allelas and the high frequency of the ACP^*C, ESD^*1 and GPT^*1 alleles, are some of the distinguishing features of Sarakatsans. Furthermore, the Sarakatsans are not a high risk population for G6PD deficiency and haemoglobinopathies.     

A linkage study of hereditary ataxias and related disorders

Genetic markers controlled by 21 genetic systems were studied in 13 families containing members suffering from various hereditary disorders involving ataxia. Classical cerebellar ataxia was present in four, Friedreich ataxia in two, hereditary spastic paraplegia in four, and the Charcot-Marie-Tooth syndrome in three families. In each family, every available member above the lowest age at onset observed in that family, was subjected to a thorough clinical investigation and blood was sampled for investigation of genetic markers.The families with cerebellar ataxia and with Charcot-Marie-Tooth syndrome contained enough informative relatives to allow a formal linkage study using the lodscore method. Three of the pedigress with cerebellar ataxia gave evidence of linkage between the disease and the HLA system with a combined lodscore of 2.128 at a recombination fraction of 0.05 for both sexes combined. The recombination fraction was considerably higher in females than in males, although the difference between the two sexes was not statistically significant.Negative lodscores were obtained for the remaining family with cerebellar ataxia, which might be due to the fact that this family only provided information on recombination in females. However, the clinical features in this family differed from those in the other three families by a significantly higher frequency of dementia and pyramidal tract lesions. Based on these observations and on contradictory results in the literature concerning linkage between cerebellar ataxia and HLA, we suggest that there are two forms of cerebellar ataxia: One (CA¹) linked to HLA with symptoms restricted to lesions in the cerebellum and spinocerebellar system and another (CA²) not linked to HLA with symptoms from more wide-spread lesions of the CNS.None of the other genetic markers (except perhaps GLO) showed linkage to the cerebellar ataxias. Negative lodscores throughout with all 21 genetic markers were found in the families with Charcot-Marie-Tooth syndrome.There was no evidence for linkage between HLA on the one hand and Friedreich ataxia or hereditary spastic paraplegia on the other.List of Abbreviations HA Hereditary ataxias - HLA Major histocompatibility system - CA Cerebellar ataxia - FA Friedreich ataxia - HSP Hereditary spastic paraplegia - CMT Charcot-Marie-Tooth syndrome - MS Multiple sclerosis - Hp Haptoglobin - Gc Group-specific component - PGM Phosphoglucomutase, locus 1 - SP (AcP) Acid phosphatase - AK Adenylatekinase - PGD 6-phosphogluconatedehydrogenase - ADA Adenosinedeaminase - GPT Glutamate pyruvat transaminase - GT Galaktose-1-phosphat uridylyltransferase - EsP Carboxylesterase D - GLO Glyoxylase I This study was aided by grants from Warwara Larsen's Foundation, the Danish Multiple Sclerosis Society and the Medical Research Council     

Some red cell enzyme phenotype frequencies in Chinese

Summary Eight enzymes: phosphoglycerate kinase, soluble glutamic oxaloacetic transaminase, glutamic-pyruvic transaminase, isocitric dehydrogenase, adenosine deaminase, peptidase A, peptidase B, and indophenol oxidase were examined electrophoretically in red cells from 160 Taiwanese samples. Only GPT and ADA were found to exhibit polymorphism, the gene frequency for GPT¹ and ADA¹ being about 0.51 and 0.95 respectively. No S-GOT variation was identified in this particular population, although an atypical gene frequency of 0.02 was anticipated from prior surveys of Asiatic groups. These samples were collected in 1960 and preserved in glycerol indicating that meaningful results can be obtained on specimens stored for prolonged periods.

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Zusammenfassung Acht Enzyme wurden in roten Blutzellen von 160 Bewohnern von Taiwan bestimmt: Phosphoglycerat-Kinase; lösliche Glutamin-Oxalessigsäure-Transaminase (S-GOT); Glutamin-Brenztramidensäure-Transaminase (GPT); Isocitronensäure-Dehydrogenase; Adenosin-Deaminase (ADA); Peptidase A; Peptidase B; Indophenol-Oxidase. Nur GPT und ADA zeigten einen Polymorphismus; die Genhäufigkeiten für GPT¹ und ADA¹ lagen bei 0,51 bzw. 0,95. Bei dieser speziellen Bevölkerung wurde keine Variation der S-GOT festgestellt, obwohl eine Genhäufigkeit für das atypische Allel von 0,02 auf Grund früherer Untersuchungen bei asiatischen Bevölkerungen erwartet worden war. Die untersuchten Stichproben waren 1960 gesammelt worden und wurden seitdem in Glycerin aufbewahrt. Dies zeigt, daß vernünftige Ergebnisse auch mit Blutproben erarbeitet werden können, die für längere Zeit aufbewahrt wurden.

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Supported by Public Health Service grant AM 09745 and by grant GM 15253 from The National Institute of Health.     

Linkage between complement components 6 and 7 and glutamic pyruvate transaminase in the marsupialMonodelphis domestica

The sixth and seventh components of complement were found to be polymorphic and tightly linked in the laboratory opossum (Monodelphis domestica), as they are in eutherian mammals. In addition, strong evidence for linkage of theC6–C7 haplotype to the gene for glutamic pyruvate transaminase (GPT) was obtained for females but not for males. This result, combined with previous observations, establishes as a generality that recombination is severely reduced in females of this species by comparison with males. It also establishes synteny ofC6–C7 andGPT in a marsupial species, as exists in mice. Because these loci are not syntenic in humans, the results imply that this synteny is ancestral to the separation of marsupials and eutherians and that it was broken relatively recently in the mammalian lineage leading to human beings. The newly described C6 and C7 polymorphisms provide additional power for developing a linkage map for M. domestica and for localizing genes that confer susceptibility to diseases for which this species is used as a model.This work was supported in part by grants from the Robert J. Kleberg, Jr., and Helen C. Kleberg Foundation and the Samuel Roberts Noble Foundation, Inc.     

Genetic Mapping of Novel Loci Affecting Canine Blood Phenotypes

Since the publication of the dog genome and the construction of high-quality genome-wide SNP arrays, thousands of dogs have been genotyped for disease studies. For many of these dogs, additional clinical phenotypes are available, such as hematological and clinical chemistry results collected during routine veterinary care. Little is known about the genetic basis of variation in blood phenotypes, but this variation may play an important role in the etiology and progression of many diseases. From a cohort of dogs that had been previously genotyped on a semi-custom Illumina CanineHD array for various genome-wide association studies (GWAS) at Cornell University Hospital for Animals, we chose 353 clinically healthy, adult dogs for our analysis of clinical pathologic test results (14 hematological tests and 25 clinical chemistry tests). After correcting for age, body weight and sex, genetic associations were identified for amylase, segmented neutrophils, urea nitrogen, glucose, and mean corpuscular hemoglobin. Additionally, a strong genetic association (P = 8.1×10⁻¹³) was evident between a region of canine chromosome 13 (CFA13) and alanine aminotransferase (ALT), explaining 23% of the variation in ALT levels. This region of CFA13 encompasses the GPT gene that encodes the transferase. Dogs homozygous for the derived allele exhibit lower ALT activity, making increased ALT activity a less useful marker of hepatic injury in these individuals. Overall, these associations provide a roadmap for identifying causal variants that could improve interpretation of clinical blood tests and understanding of genetic risk factors associated with diseases such as canine diabetes and anemia, and demonstrate the utility of holistic phenotyping of dogs genotyped for disease mapping studies.     

Distribution of hereditary blood groups among Indians in South America. I. In Ecuador

Blood specimens were procured from 658 Quechua, 36 Colorado, 233 Jivaro, 244 Cayapa, and 48 Secoya Indians of Ecuador. These were examined for antigens in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, K-k, Lewis, Duffy and Kidd systems and for Diego (Di^a), Wright (Wr^a), and Berrens (Be^a) agglutinogens as well. Hemolystes were prepared and studied for hemoglobin types and the serum samples were tested for haptoglobins and transfserrins. Gene frequencies are high for O, M, s, R¹, (CDe), R² (cDE), Lu^b, k, Kp^b, Le^b and Fy^a; and low or absent for A, B, N, S, Mi^a, Vw, Mt^a, R⁰ (cDe), V (ce^s), Lu^a, K, Kp^a, Le^a, Fy^b, Js^a, Wr^a and Be^a. The Diego (Di^a) gene is present but its frequency varies greatly from tribe to tribe. Gene frequency Hp¹ is well within the range previously reported for Indians in Middle America excepting the Colorado in which population the frequency of 0.889 is unusually high. All 723 serum specimens tested for transferrins were C or CD. No D or BC types were found. All Ecuadorian Indian bloods tested electrophoretically contained only hemoglobin (A) as a major component.     

Distribution of blood groups among indians in South America. VI. In Paraguay

This paper on the distribution of hereditary factors in the blood of Indians in South America, reports the results of tests made on samples procured from Paraguayan Indians. Specimens from putatively full-blood persons were obtained from the following tribes: 88 Chamacoco, 36 Moro, 85 Chulupi, 207 Lengua, 100 Toba, 20 Yam Lengua, and 51 Guayaki, These 587 Samples were tested for factors in the A-B-O, M-N-S-s, P. Rh-Hr, Lutheran, Kell-Cellano, Lewis, Duffy, Kidd, and Diego systems. Serum samples were tested for haptoglobins and transferrins. He molysates, prepared from whole blood, were tested for hemoglobin types. The results are presented on appropriate tables as number and per cent of phenotypes for the various blood group antigens and their calculated allele frequencies. Locations of the populations from which blood samples were procured are listed on the tables and shown on a map (fig. 1). Of the 587 samples all except two Chamacoco belonged to group O. High frequencies are reported generally for M, s, P, R¹ (CDe), R² (cDE), k (100%) and Fy alleles in Paraguayn Indians. Low frequencies were generally reported for N, S, r (cde) and R° (cDe) alleles. There was a wide variation in frequencies for Di, Jk, and haptoglobin Hp¹. All tested for transferrins were classified as Tf C and all contained hemoglobin (A) as a major component. The following antigens were completely absent: Mi^a, Vw, p, P^k, r^y (CdE), K, and Le¹. Most notable is the unusual distribution of hereditary blood antigens among the Guayaki and Moro. The Guayaki had 100% P₁ and Fy^a; they were higher in R° (cDe), R¹ (CDe), and Jk^a; and lower in R² (cDE) and Hp¹ genes than other Indians; and Di was absent. The Guayaki differed from the other Indians also in having fair skin. The Moro were lower in the P¹ and Jk gene frequencies than is usually found in Amerinds, and the Di gene was absent. The Chamacoco also had an exceptionally low frequency for the P¹ gene (0.261).     

Distribution of hereditary blood groups among Indians in South America. IV. In Chile with inferences concerning genetic connections between Polynesia and America

This is the fourth paper in a series on the distribution of blood groups among Indians of South America. It reports the findings on the Indians of Chile and the Polynesians of Chile's Easter Island. Blood specimens were procured from the following putatively pure Indians and unmixed Polynesians: 44 Alacaluf of Puerto Eden, Isla Wellington, 141 Mapuche (Araucanian) of Lonquimay, Malleco Province, 80 Atacameños of Antofagasta Province, and 45 Polynesians of Easter Island. These 310 samples were tested for blood factors in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, K-k, Lewis, Duffy, Kidd and Diego systems, and for the Wright (Wr^a) agglutinogen. Serum samples were tested for haptoglobins and transferrins. Hemolysates prepared from the blood clots were tested for hemoglobin types. The results are presented as phenotype incidences and calculated gene frequencies in appropriate tables. Locations of the populations from which blood samples were procured are shown on two maps. The high frequencies for the O gene usually reported for South American Indians obtain in putatively pure Chilean Indians but A¹ is high in Easter Island Polynesians. In both Indians and Polynesians M, s, R¹ (CDe), R² (cDE), Lu^b, k, Le^H, and Fy^a gene frequencies are high and B, N, S, Mi^a, Vw, Rº (cDe), r (cde), Lu^a, K, Le¹, Fy^b, and Wr^a (Ca) are low or absent. The Diego (Di) gene is present in the Mapuche and Atacameños but absent in the Alacaluf and Polynesians. Hp¹ gene frequencies were determined only in the Alacaluf and Atacameños, in which they are 0.48 and 0.67 respectively. Transferrins were determined for the Alacaluf and Atacameños Indians and all were classified as Tf C. All Chilean Indian and Polynesian specimens were tested electrophoretically for hemoglobin types and all contained only hemoglobin (A) as a major component.     

Enzyme immunoassays of N 6-benzyladenine and N 6-(meta-hydroxybenzyl)adenine cytokinins

Enzyme-linked immunosorbent assays (ELISAs) were developed for determination of N ⁶-benzyladenosine, N ⁶-(meta-hydroxybenzyl)adenosine, and structurally related cytokinins. The use of the ELISAs allowed detection over the range of 0.05–70 pmol for N ⁶-benzyladenine and 0.01–20 pmol for the N ⁶-(meta-hydroxybenzyl)adenine cytokinins. Polyclonal antibodies used in the assays were specific for N ⁶-benzyladenine and N ⁶-(meta-hydroxybenzyl)adenine and their corresponding N ⁹-substituted derivatives. By the use of internal standardization, dilution assays, authentic [2-³H]cytokinin recovery markers, and immunohistograms, the ELISAs have been shown to be applicable for the estimation of N ⁶-benzyladenine and N ⁶-(meta-hydroxybenzyl)adenine-type cytokinins in plant tissues. For the analysis of cytokinins in the tissues of young poplar leaves and Solarium teratoma shoot culture, the extracts were fractionated by high performance liquid chromatography (HPLC) and the fractions analyzed by ELISAs. Immunohistogram ELISA analysis of fractions from different HPLC systems indicated major peaks of immunoreactivity co-chromatographing with the labeled and unlabeled standards of N ⁶-benzyladenine, N ⁶-meta-hydroxybenzyl)adenine, and their N ⁹-glycosides in these tissues.Abbreviations ELISA enzyme-linked immunosorbent assay - FW fresh weight - (mOH)[9R]BAP N ⁶-(meta-hydroxybenzyl)adenosine - HPLC high performance liquid chromatography - TBS Tris-buffered saline - TEAA triethylammonium acetate - [9R]BAP N ⁶-benzyladenosine