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PubMed2002

Developmentally regulated dual-specificity kinase from peanut that is induced by abiotic stresses.

Tyrosine (Tyr) phosphorylation represents an important biochemical mechanism to regulate many cellular processes. No Tyr kinase has been cloned so far in plants. Dual-specificity kinases are reported in plants and the function of these kinases remains unknown. A 1.7-kb cDNA that encodes serine/threonine/Tyr (STY) kinase was isolated by screening peanut (Arachis hypogaea) expression library using the anti-phospho-Tyr antibody. The histidine-tagged recombinant kinase histidine-6-STY predominantly autophosphorylated on Tyr and phosphorylated the histone primarily on threonine. Genomic DNA gel-blot analysis revealed that STY kinase is a member of a small multigene family. The transcript of STY kinase is accumulated in the mid-maturation stage of seed development, suggesting a role in the signaling of storage of seed reserves. The STY kinase mRNA expression, as well as kinase activity, markedly increased in response to cold and salt treatments; however, no change in the protein level was observed, suggesting a posttranslational activation mechanism. The activation of the STY kinase is detected after 12 to 48 h of cold and salt treatments, which indicates that the kinase may not participate in the initial response to abiotic stresses, but may play a possible role in the adaptive process to adverse conditions. The transcript levels and kinase activity were unaltered with abscisic acid treatment, suggesting an abscisic acid-independent cold and salt signaling pathway. Here, we report the first identification of a non-MAP kinase cascade dual-specificity kinase involved in abiotic stress and seed development.

Amino Acid Sequence↗

PubMed2003

Microspore separation in the quartet 3 mutants of Arabidopsis is impaired by a defect in a developmentally regulated polygalacturonase required for pollen mother cell wall degradation.

Mutations in the QUARTET loci in Arabidopsis result in failure of microspore separation during pollen development due to a defect in degradation of the pollen mother cell wall during late stages of pollen development. Mutations in a new locus required for microspore separation, QRT3, were isolated, and the corresponding gene was cloned by T-DNA tagging. QRT3 encodes a protein that is approximately 30% similar to an endopolygalacturonase from peach (Prunus persica). The QRT3 protein was expressed in yeast (Saccharomyces cerevisiae) and found to exhibit polygalacturonase activity. In situ hybridization experiments showed that QRT3 is specifically and transiently expressed in the tapetum during the phase when microspores separate from their meiotic siblings. Immunohistochemical localization of QRT3 indicated that the protein is secreted from tapetal cells during the early microspore stage. Thus, QRT3 plays a direct role in degrading the pollen mother cell wall during microspore development.

Amino Acid Sequence↗

PubMed2003

Conserved subgroups and developmental regulation in the monocot rop gene family.

Rop small GTPases are plant-specific signaling proteins with roles in pollen and vegetative cell growth, abscisic acid signal transduction, stress responses, and pathogen resistance. We have characterized the rop family in the monocots maize (Zea mays) and rice (Oryza sativa). The maize genome contains at least nine expressed rops, and the fully sequenced rice genome has seven. Based on phylogenetic analyses of all available Rops, the family can be subdivided into four groups that predate the divergence of monocots and dicots; at least three have been maintained in both lineages. However, the Rop family has evolved differently in the two lineages, with each exhibiting apparent expansion in different groups. These analyses, together with genetic mapping and identification of conserved non-coding sequences, predict orthology for specific rice and maize rops. We also identified consensus protein sequence elements specific to each Rop group. A survey of ROP-mRNA expression in maize, based on multiplex reverse transcriptase-polymerase chain reaction and a massively parallel signature sequencing database, showed significant spatial and temporal overlap of the nine transcripts, with high levels of all nine in tissues in which cells are actively dividing and expanding. However, only a subset of rops was highly expressed in mature leaves and pollen. Intriguingly, the grouping of maize rops based on hierarchical clustering of expression profiles was remarkably similar to that obtained by phylogenetic analysis. We hypothesize that the Rop groups represent classes with distinct functions, which are specified by the unique protein sequence elements in each group and by their distinct expression patterns.

Amino Acid Sequence↗

PubMed2005

Functional interaction between two transcription factors involved in the developmental regulation of a small heat stress protein gene promoter.

Hahsp17.6G1 is the promoter of a small heat stress protein (sHSP) from sunflower (Helianthus annuus) that is activated during zygotic embryogenesis, but which does not respond to heat stress. We report here the cloning of a transcription factor (TF), sunflower drought-responsive element binding factor 2 (HaDREB2), by one-hybrid interaction with functional cis-elements in Hahsp17.6G1. We have analyzed the functional interaction between HaDREB2 and a second transcription factor, sunflower heat stress factor A9 (HaHSFA9), which was previously assigned to the regulation of Hahsp17.6G1. HaDREB2 and HaHSFA9 synergistically trans-activate the Hahsp17.6G1 promoter in bombarded sunflower embryos. This synergistic interaction is heat stress factor (HSF) specific and requires the binding of both factors to the promoter. The C-terminal region of HaHSFA9 is sufficient for the HSF specificity. Our results represent an example of a functional interaction between members of the Apetala 2 (HaDREB2) and HSF (HaHSFA9) families of transcription factors. We suggest new roles in zygotic embryogenesis for specific members of the AP2 transcription factor family.

Amino Acid Sequence↗

PubMed1998

A gene encoding proline dehydrogenase is not only induced by proline and hypoosmolarity, but is also developmentally regulated in the reproductive organs of Arabidopsis.

The cDNA clone ERD5 (early responsive to dehydration), isolated from 1-h-dehydrated Arabidopsis, encodes a precursor of proline (Pro) dehydrogenase (ProDH), which is a mitochondrial enzyme involved in the first step of the conversion of Pro to glutamic acid. The transcript of the erd5 (ProDH) gene was undetectable when plants were dehydrated, but large amounts of transcript accumulated when plants were subsequently rehydrated. Accumulation of the transcript was also observed in plants that had been incubated under hypoosmotic conditions in media that contained L- or D-Pro. We isolated a 1.4-kb DNA fragment of the putative promoter region of the ProDH gene. The beta-glucuronidase (GUS) reporter gene driven by the 1.4-kb ProDH promoter was induced not only by rehydration but also by hypoosmolarity and L- and D-Pro at significant levels in transgenic Arabidopsis plants. The promoter of the ProDH gene directs strong GUS activity in reproductive organs such as pollen and pistils and in the seeds of the transgenic plants. GUS activity was detected in vegetative tissues such as veins of leaves and root tips when the transgenic plants were exposed to hypoosmolarity and Pro solutions. GUS activity increased during germination of the transgenic plants under hypoosmolarity. The relationship between Pro metabolism and the physiological aspects of stress response and development are discussed.

Arabidopsis↗

PubMed1999

The wheat peptidyl prolyl cis-trans-isomerase FKBP77 is heat induced and developmentally regulated.

We isolated a cDNA encoding a 568-amino acid, heat-stress-induced peptidyl prolyl isomerase belonging to the FK506-binding-protein (FKBP) family. The open reading frame encodes for a peptidyl prolyl isomerase that possesses three FKBP-12-like domains, a putative tetratricopeptide motif, and a calmodulin-binding domain. Specific antibodies showed that the open reading frame encodes a heat-induced 77-kD protein, the wheat FKBP77 (wFKBP77), which exhibits 84% identity with the wFKBP73 and 42% identity with the human FKBP59. Because of the high similarity in sequence to wFKBP73, wFKBP77 was designated as the heat-induced isoform. The wFKBP77 mRNA steady-state level was 14-fold higher at 37 degreesC than at 25 degreesC. The wFKBP77 transcript abundance was the highest in mature embryos that had imbibed and 2-d-old green shoots exposed to 37 degreesC, and decreased to 6% in 6-d-old green shoots. The transcript level returned to the level detected at 25 degreesC after recovery of the embryos for 90 min at 25 degreesC. We compared wFKBP73 and wFKBP77 with the heat-shock proteins having cognate and heat-stress-induced counterparts.

Amino Acid Sequence↗

PubMed1997

Developmentally regulated expression of the CYP4A genes in the spontaneously hypertensive rat kidney.

The CYP4A enzymes catalyze the formation of 20-hydroxyeicosatetraenoic acid (20-HETE), which has potent effects on the renal vasculature and tubular ion transport. Based on an increased 20-HETE formation in renal microsomes from spontaneously hypertensive rats, it has been proposed that increased expression of the CYP4A genes is an early event in the development of hypertension in these animals. To test this hypothesis, we developed RNase protection assays for specific detection of the individual CYP4A genes in the kidneys of spontaneously hypertensive and Wistar-Kyoto rats. Distinct age-dependent patterns of expression were observed for the individual CYP4A genes, with only CYP4A3 mRNA measurable in the kidneys of 1-week-old rats. CYP4A1 and CYP4A8 mRNA were detectable by 3 weeks of age and CYP4A2 mRNA at 5 weeks of age. The expression of CYP4A1 and CYP4A3 varied 4-5-fold throughout development and was highest between 3 and 5 weeks of age, declining steadily thereafter to 20% of their maximal level by 9 weeks of age. CYP4A2 mRNA levels increased steadily between 5 and 9 weeks of age, whereas CYP4A8 mRNA levels were relatively constant throughout development. The CYP4A3 mRNA level was significantly increased 1. 6-2-fold in the cortex and outer medulla of 1-4-week-old spontaneously hypertensive rat kidneys relative to the corresponding level in the Wistar-Kyoto. A similar 1.4-1.7-fold increase in CYP4A8 mRNA was also found in 3- and 4-week-old spontaneously hypertensive kidneys. Accompanying the increased expression of CYP4A3 and CYP4A8 mRNA in the prehypertensive rats were corresponding changes in functional CYP4A measured as either arachidonic acid or lauric acid omega-hydroxylase activity (1.4-2.0-fold increases) and CYP4A protein levels. After 4 weeks of age, the level of CYP4A mRNA, enzyme activity, and protein were similar in the kidneys of Wistar-Kyoto and spontaneously hypertensive rats. The findings suggest that the expression of CYP4A3 and CYP4A8 may be critical to the early changes in eicosanoid formation and renal function in the young spontaneously hypertensive rat.

Animals↗

PubMed2006

GAS2 and GAS4, a pair of developmentally regulated genes required for spore wall assembly in Saccharomyces cerevisiae.

The GAS multigene family of Saccharomyces cerevisiae is composed of five paralogs (GAS1 to GAS5). GAS1 is the only one of these genes that has been characterized to date. It encodes a glycosylphosphatidylinositol-anchored protein functioning as a beta(1,3)-glucan elongase and required for proper cell wall assembly during vegetative growth. In this study, we characterize the roles of the GAS2 and GAS4 genes. These genes are expressed exclusively during sporulation. Their mRNA levels showed a peak at 7 h from induction of sporulation and then decreased. Gas2 and Gas4 proteins were detected and reached maximum levels between 8 and 10 h from induction of sporulation, a time roughly coincident with spore wall assembly. The double null gas2 gas4 diploid mutant showed a severe reduction in the efficiency of sporulation, an increased permeability of the spores to exogenous substances, and production of inviable spores, whereas the single gas2 and gas4 null diploids were similar to the parental strain. An analysis of spore ultrastructure indicated that the loss of Gas2 and Gas4 proteins affected the proper attachment of the glucan to the chitosan layer, probably as a consequence of the lack of coherence of the glucan layer. The ectopic expression of GAS2 and GAS4 genes in a gas1 null mutant revealed that these proteins are redundant versions of Gas1p specialized to function in a compartment at a pH value close to neutral.

Cell Wall↗

PubMed2001

The mouse Na+-K+-ATPase gamma-subunit gene (Fxyd2) encodes three developmentally regulated transcripts.

The Na(+)-K(+)-ATPase is understood to function as a hetero-oligomer of alpha- and beta-subunits, but a third subunit, gamma, has been proposed to influence the enzyme's catalytic function. Recently, two variants of the gamma-subunit have been described in kidney, raising the possibility of multiple gamma-subunits with diverse functions. We now report the cloning and sequencing of the mouse gamma-subunit gene (Fxyd2). Analysis of the structure of the gene shows that it encodes three mRNAs that have distinct NH(2)-terminal (extracellular) encoding sequences but common transmembrane and COOH-terminal-encoding sequences resulting from differential splicing and, probably, alternate promoter usage. The three mRNAs have tissue-specific expression patterns. The existence of three different extracellular domains of the gamma-variants and how they may interact with the sodium pump to alter its cation transport properties must now be taken into account for future understanding of the modulation of the Na(+)-K(+)-ATPase by its gamma-subunit.

Alternative Splicing↗

PubMed1999

Developmental regulation of nitric oxide synthase expression in rat skeletal bone.

Nitric oxide (NO) has been implicated in bone growth and remodeling by studies showing that inhibition of NO-synthase (NOS) activity retards normal gain in bone mineral density both during skeletal development and after sexual maturity. In the present study, we aimed to assess the level of expression and cellular localization of the three NOS isoforms during skeletal bone development from neonatal to sexual maturity in female Wistar rats. Reverse transcription polymerase chain reaction (RT-PCR) was used to analyze the presence of NOS1 (neuronal), NOS2 (inducible), and NOS3 (endothelial) transcripts in femoral bone from neonatal, 4-, 8-, and 12-week-old rats. RT-PCR amplified NOS1, NOS2, and NOS3 transcripts of 472-, 807-, and 289-bp, respectively. There were no detectable differences in the levels of NOS1 mRNA between the groups; however, NOS2 mRNA was more abundant in the neonatal group compared with 4-, 8-, and 12-week groups. Expression of NOS1 protein could not be detected in bones by either Western blotting or immunocytochemistry in any of the age groups investigated. Western blots for NOS2 revealed expression in the neonatal group only and it was not detected in any of the older age groups. Immunostaining for NOS2 was also most evident in the neonatal group and was localized specifically to trabecular osteoblasts and osteoclasts. In all age groups studied, NOS3 mRNA and protein were found in bone-resorbing osteoclasts, cuboidal active osteoblasts, and osteocytes. Semiquantitative RT-PCR provided evidence of down-regulation of NOS3 transcripts during the skeletal development. This was confirmed using in situ hybridization, which showed higher expression in neonatal and 4-week groups than in other groups. Western blots and counting the ratio of trabecular osteoblasts that were NOS3 immunoreactive showed parallel down-regulation of NOS3 protein during skeletal development. Taken together, these data show that there is regulation of NOS2 and in particular NOS3 expression during skeletal development and this may be significant to trabecular bone growth and remodeling.

Animals↗

PubMed2000

Characterization of blue-light and developmental regulation of the photolyase gene phr1 in Trichoderma harzianum.

Blue light and development regulate the expression of the phr1 gene of the filamentous fungus Trichoderma harzianum. The predicted product of phr1, the DNA repair enzyme photolyase, is likely to help protect Trichoderma, which grows in the soil as a mycoparasite or saprophyte, from damage upon emergence and exposure to ultraviolet-c. phr1 is transiently expressed in mycelium and conidiophores after illumination. phr1 mRNA also accumulates in conidiophores during development and spore maturation. As no other genes displaying rapid, direct light regulation have been described previously in this organism, we have characterized the fluence and time dependence of phr1 induction, and its relation to sporulation and photoreactivation. Induction is transient following a pulse, and, with slower decay, in continuous light. This implies that the photoreceptor, transducers or response are capable of adaptation. About two-fold more light is required to induce phr1 than conidiation, but this difference is modest, so both responses could use the same or similar chromophore. Adenosine 3':5'-cyclic monophosphate bypasses the requirement for light for sporulation, while atropine prevents sporulation even after photoinduction. Light regulation of phr1, however, is indifferent to both these effectors. Induction of photolyase expression behaves as a direct, rapid response to light, independent of the induction of sporulation. Indeed, illumination of mature spores increases their capacity for photoreactivation. Blue light seems to warn the organism against the harmful effects of short wave-lengths, inducing phr1 expression and sporulation by pathways that are, at least in part, distinct.

Deoxyribodipyrimidine Photo-Lyase↗

PubMed2001

Developmental regulation of alternatively spliced acetyl-CoA carboxylase-alpha mRNAs encoding isozymes with or without an eight amino acid domain upstream of the Ser-1200 phosphorylation motif in the mammary gland.

Expression of a variant acetyl-CoA carboxylase-alpha (ACC-alpha) mRNA encoding an isozyme either comprising (+24nt) or lacking (Delta24nt) an eight amino acid domain proximal to the Ser-1200 phosphorylation motif has been investigated in ovine and rat mammary tissue throughout pregnancy and lactation. The ratio of the Delta24nt mRNA: +24nt mRNA in ovine tissues varied from 0.1-0.25 (spleen, lung, muscle, heart, adipose tissue, brain) to 0.6-0.8 (pancreas, liver, kidney) to approximately 5.0 (lactating mammary gland). The sixfold increase in total ACC-alpha mRNA expression in mammary gland during lactation was due entirely to a tenfold increase in the level of the Delta24nt species as the level of expression of the +24nt species remained unaltered between pregnancy and lactation. This mode of expression of the +24nt and Delta24nt mRNAs was similar in rat mammary gland. Between day 20 of pregnancy and day 4 of lactation the ratio of the Delta24nt : +24nt mRNA increased from 2:1 to 10-20:1. Forced involution reduced the ratio of the two mRNAs to levels observed throughout pregnancy. Treatment of lactating rats with bromocryptine reduced the ratio of the Delta24nt : +24nt mRNA to relative levels observed after forced involution, suggesting that the exonic splicing responsible for the generation of the two mRNA isoforms is prolactin responsive.

Acetyl-CoA Carboxylase↗

PubMed1999

PTPROt: an alternatively spliced and developmentally regulated B-lymphoid phosphatase that promotes G0/G1 arrest.

Protein tyrosine phosphatases (PTP) regulate the proliferation, differentiation, and viability of lymphocytes by modulating their signaling pathways. By using the differential display assay, we have cloned a putative receptor-type PTP, which is predominantly expressed in B-lymphoid tissues (lymph nodes and spleen). This PTP, termed PTPROt (truncated), is a tissue-specific alternatively-spliced form of a human epithelial PTP, PTPRO (PTPU2/GLEPP1). Whereas the epithelial PTPRO includes an approximately 800-amino acid extracellular domain, the major (3 kb) PTPROt cDNA predicts a unique 5' untranslated region and truncated (8 amino acids) extracellular domain with a conserved transmembrane region and single catalytic domain. PTPROt cDNAs encode functional approximately 47-kD and approximately 43-kD PTPs, which are most abundant in normal naive quiescent B cells and decreased or absent in germinal center B cells and germinal center-derived diffuse large B-cell lymphomas. Because PTPROt was predominantly expressed in naive quiescent B cells, the enzyme's effects on cell-cycle progression were examined. When multiple stable PTPROt sense, antisense, and vector only B-cell transfectants were grown in reduced serum and synchronized with nocodazole, PTPROt sense clones exhibited markedly increased G0/G1 arrest. Taken together, these data implicate PTPROt in the growth control of specific B-cell subpopulations.

Alternative Splicing↗

PubMed1986

Characterization and cellular localization of a developmentally regulated rat neural sialidase.

A developmentally regulated neural sialidase has been identified in particulate, subcellular fractions of rat brain. Enzyme activity, measured using a [3H]sialoganglioside substrate, was linear with time and had a pH optimum of 4.0-4.5. Protein linearity was only observed at low protein concentrations. This appeared to be caused by enzyme access to a lipophilic substrate, as activity was significantly stimulated by membrane-fluidizing agents. Enzyme activity was developmentally expressed in P2 pellets coincident with in vivo synaptogenesis. It was located on the synaptosome and was particularly high in myelin-containing fractions. Its cellular distribution was confined to neuronal cells and centrally derived oligodendrocytes.

Animals↗

PubMed1999

Identification and expression analysis of two developmentally regulated myosin heavy chain gene transcripts in carp (Cyprinus carpio).

Whilst developmentally regulated genes for the myosin heavy chain (MyoHC) have been characterised in mammalian, avian and amphibian species, no developmental MyoHC gene has previously been characterised in a species of fish. In this study, we identify two developmentally regulated MyoHC gene transcripts (named Eggs22 and Eggs24) in carp (Cyprinus carpio) and characterise their expression patterns during embryonic and larval development. The transcripts showed an identical temporal pattern of expression commencing 22 h post-fertilisation (18 degrees C incubation temperature), coincident with the switch from exclusive expression of genes for beta-actin to expression of genes for both beta- and alpha-actin, and continuing for 2 weeks post-hatching. No expression of these myosin transcripts was detected in juvenile or adult carp. Wholemount in situ hybridisation showed that both transcripts are expressed initially in the rostral region of the developing trunk and progress caudally. Both are expressed in the developing pectoral fin and protractor hyoideus muscles. However, the muscles of the lower jaw express only the Eggs22 transcript. No expression of either transcript was detected in cardiac or smooth muscle. A distinct chevron pattern of expression was observed in the myotomal muscle. This was shown to be caused by localisation of the mRNAs to the myoseptal regions of the fibres, the sites of new sarcomere addition during muscle growth, suggesting transport of MyoHC mRNA transcripts. The 3' untranslated region of the Eggs24 transcript contains a 10 base pair motif (AAAATGTGAA) which is shown to be also present in the 3' untranslated regions of MyoHC genes from a wide range of species. Possible reasons for the need for developmental isoforms of myosin heavy chain isoforms are discussed.

Amino Acid Sequence↗

PubMed1992

Guide RNAs for transcripts with developmentally regulated RNA editing are present in both life cycle stages of Trypanosoma brucei.

RNA editing of several mitochondrial transcripts in Trypanosoma brucei is developmentally regulated. The cytochrome b and cytochrome oxidase II mRNAs are edited in procyclic-form parasites but are primarily unedited in bloodstream forms. The latter forms lack the mitochondrial respiratory system present in procyclic forms. Editing of the NADH dehydrogenase 7 (ND7) and ND8 transcripts is also developmentally regulated but occurs preferentially in bloodstream forms. Other transcripts, cytochrome oxidase III and ATPase 6, are edited in both life forms. We have identified many minicircle-encoded guide RNAs (gRNAs) for ATPase 6, ND7, and ND8. The characteristics of these gRNAs reveal how extensively edited RNA can be edited in the 3'-to-5' direction. Northern (RNA) blot and primer extension analyses indicate that gRNAs for transcripts whose editing is developmentally regulated are present in both procyclic and bloodstream form parasites. These results suggest that the developmental regulation of editing in these transcripts is not controlled by the presence or absence of gRNAs.

Aging↗

PubMed1997

Developmental regulation of the sulfation profile of chondroitin sulfate chains in the chicken embryo brain.

Developmentally regulated and cell type-specific expression of distinct sulfated glycosaminoglycan structures on cell surface proteoglycans is increasingly recognized as providing information relevant to cell-cell interactions and differentiation in developing organisms. In this report, developmental regulation of both the sulfation profile of chondroitin sulfate chains and activities of chondroitin 4-sulfotransferase (C4ST) and chondroitin 6-sulfotransferase (C6ST) were evaluated in embryonic chicken brain. The results revealed that the sulfation profile and the sulfotransferase activities changed markedly with development, and these alterations were precisely coordinated. Specifically, the proportions of both chondroitin 6-sulfate to 4-sulfate and C6ST to C4ST activities progressively decreased with development. In addition, the total amounts of both chondroitin sulfate chains and the sulfotransferase activities were highest during early embryonic stages and decreased sharply as the development reached completion. The developmental expression of the C6ST gene was also found to parallel the developmental down-regulation of both the C6ST activity and the chondroitin 6-sulfate structure. These findings suggest that the developmentally regulated expression of the sulfotransferases is a predominant factor for stage-specific regulation of chondroitin sulfate structures.

Animals↗

PubMed1999

The 2.15 A crystal structure of CG-16, the developmentally regulated homodimeric chicken galectin.

Differential developmental regulation of expression, fine-specificity differences in ligand recognition and disparate capacity for homodimerization are characteristics of the two currently known proto-type chicken galectins. The X-ray crystal structure of the first avian galectin, the homodimeric agglutinin from chicken liver (CG-16), has been solved in the absence of ligand in two crystal forms. Although the arrangement of lectin dimers in the two crystals is different, the structure of the monomers and their association into the extended beta-sandwich that characterises the dimer are virtually identical. The fold establishes a beta-sandwich motif composed of a five-stranded and a six-stranded beta-sheet evocative of proto-type mammalian galectins. The carbohydrate-binding site is occupied by six water molecules that take the place of the sugar in the complex. They help to stabilise in the absence of the ligand the spatial arrangement of the amino acid side-chains involved in sugar recognition. Docking of N-acetyllactosamine into the binding site reveals that three of these water molecules, which are in direct contact with the protein, occupy positions equivalent to the key sugar hydroxyl groups, namely the hydroxyls at positions 4 and 6 of the galactose unit and at position 3 of the N-acetylglucosamine unit. Crystallographic data are fully consistent with the binding features in solution previously derived from chemical mapping with deoxy, fluoro and O-methyl derivatives and laser photo-CIDNP (chemically induced dynamic nuclear polarisation) studies. The possible molecular basis for the monomeric character of the chicken intestinal galectin as well as potential mechanisms of oxidative inactivation by disulphide bridging are evaluated on the basis of the given structural information concerning the CG-16 dimer interface and the cysteine residues, respectively.

Amino Acid Sequence↗