Biochemical comparison of γ‐crystallins from duck and frog eye lenses

Chiou, Shyh‐Horng; Chang, Wen Chang; Kuo, Jane; Pan, Fu-Ming; Lo, Tung Bin

doi:10.1016/0014-5793(86)80250-2

Cited by 21 publications

(10 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Elution profiles for soluble proteins in cortical lens fractions of the frog lenses used in this study are comparable to chromatograms obtained using fractionated whole frog lenses in earlier studies []. A shortcoming of previous studies using whole lenses, which this study aimed to overcome, is that without examining lens protein in different regions of the lens, it is not possible to examine the effects of changes on crystallin synthesis, development or ageing.…”

Section: Discussionsupporting

confidence: 67%

See 1 more Smart Citation

Crystallin distribution patterns in Litoria infrafrenata and Phyllomedusa sauvagei lenses

et al. 2012

View full text Add to dashboard Cite

The eye lens remains transparent because of soluble lens proteins known as crystallins. For years γ-crystallins have been known as the main lens proteins in lower vertebrates such as fish and amphibians. The unique growth features of the lens render it an ideal structure to study ageing; few studies have examined such changes in anuran lenses. This study aimed to investigate protein distribution patterns in Litoria infrafrenata and Phyllomedusa sauvagei species. Lenses were fractionated into concentric layers by controlled dissolution. Water-soluble proteins were separated into high (HMW), middle (MMW) and low molecular weight (LMW) fractions by size-exclusion HPLC and constituents of each protein class revealed by 1DE and 2DE. Spots were selected from 2DE gels on the basis of known ranges of subunit molecular weights and pH ranges and were identified by MALDI-TOF/TOF MS following trypsin digestion. Comparable lens distribution patterns were found for each species studied. Common crystallins were detected in both species; the most prominent of these was γ-crystallin. Towards the lens centre, there was a decrease in α- and β-crystallin proportions and an increase in γ-crystallins. Subunits representing taxon-specific crystallins demonstrating strong sequence homology with ζ-crystallin/quinone oxidoreductase were found in both L. infrafrenata and P. sauvagei lenses. Further work is needed to determine which amphibians have taxon-specific crystallins, their evolutionary origins, and their function.

show abstract

Section: Discussionsupporting

confidence: 67%

“…Studies examining proteins from a range of species provide information on their evolutionary history []. Soluble lens proteins have been investigated extensively in a range of mammals, however, information derived from amphibian lenses is more scarce [].…”

Section: Introductionmentioning

confidence: 99%

Crystallin distribution patterns in Litoria infrafrenata and Phyllomedusa sauvagei lenses

et al. 2012

View full text Add to dashboard Cite

show abstract

“…In frog lenses of genera Rana, the taxon-specific protein r-crystallin has been isolated. This protein is a monomeric crystallin with a molecular weight around 37 kDa [15][16][17][18][19]. z-crystallin, originally detected in guinea pig eye lenses has also been found to be present in Japanese tree-frog (Hyla japonica) lenses [20,21].…”

Section: Introductionmentioning

confidence: 99%

Crystallin distribution patterns in concentric layers from toad eye lenses

et al. 2009

View full text Add to dashboard Cite

Protein distribution patterns across eye lenses from the Asiatic toad Bufo gargarizans were investigated and individual crystallin classes characterised. Special fractionation that follows the growth mode of the lens was used to yield nine fractions corresponding to layers laid down at different chronological (developmental) stages. Proportions of soluble and insoluble crystallins within each fraction were measured by Bradford assay. Water-soluble proteins in all fractions were separated by size-exclusion HPLC and constituents of each class further characterised by electrophoresis, RP-HPLC and MS analysis. In outer lens layers, alpha-crystallin is the most abundant soluble protein but is not found in soluble proteins in the lens centre. Water-soluble beta-crystallins also decrease from their highest level in the outer lens to negligible mounts in the central lens. The proportion of soluble gamma-crystallin increases significantly towards the lens centre where this is the only soluble protein present. Insoluble protein levels increase significantly towards the lens centre. In B. gargarizans lenses, as with other anurans, the predominant water-soluble protein class is gamma-crystallin. No taxon-specific crystallins were found. The relationship between the protein distribution patterns and the functional properties of the lens this species is discussed.

show abstract

“…The batch preparations of crystallins were routinely carried out from the pooled lenses of about 50 duck eyeballs. They were freshly collected from the above Institute without freezing, decapsulated, and homogenized in 20-30 ml of 0.05 M-ammonium bicarbonate buffer, pH 7.7, containing 5 mm-EDTA as described previously [11,12]. Anion-exchange chromatography on a TSK DEAE-650(M) (2.5 cm x 15 cm) (Merck, Darmstadt, Germany) column was employed for the separation of e-crystallin from &-, a-and fl-crystallins in the crude lens extract.…”

Section: Crystallin Isolation and Purificationmentioning

confidence: 99%

“…The unexpected findings that sequence similarities existed between crystallins and some metabolic enzymes, for example ecrystallin and lactate dehydrogenase (LDH) [6], p-crystallin and aldehyde/aldose reductase [7] plus bovine lung prostaglandin F synthase [8], and 8-crystallin and argininosuccinate lyase [9], have aroused a lot of interest in aspects concerning the evolution of lens crystallins and their possible enzymic functions in general. e-Crystallin has been found to be present as a minor crystallin in duck and caiman lenses [10][11][12]. It appeared to be structurally similar to avian heart-type lactate dehydrogenase [(S)lactate: NADI oxidoreductase, EC 1.1.1.27], as revealed by peptide mapping [6] and sequence comparison [13].…”

Section: Introductionmentioning

confidence: 99%

Kinetic analysis of duck ε-crystallin, a lens structural protein with lactate dehydrogenase activity

Chiou

Lee

Chang

1990

Biochemical Journal

View full text Add to dashboard Cite

Biochemical characterization and kinetic analysis of epsilon-crystallin from the lenses of common ducks were undertaken to elucidate the enzyme mechanism of this unique crystallin with lactate dehydrogenase (LDH) activity. Despite the structural similarities between epsilon-crystallin and chicken heart LDH, differences in charge and kinetic properties were revealed by isoenzyme electrophoresis and kinetic studies. Bi-substrate kinetic analysis examined by initial-velocity and product-inhibition studies suggested a compulsory ordered Bi Bi sequential mechanism with NADH as the leading substrate followed by pyruvate. The products were released in the order L-lactate and NAD+. The catalysed reaction is shown to have a higher rate in the formation of L-lactate and NAD+. Substrate inhibition was observed at high concentrations of pyruvate and L-lactate for the forward and reverse reactions respectively. The substrate inhibition was presumably due to the formation of epsilon-crystallin-NAD(+)-pyruvate or epsilon-crystallin-NADH-L-lactate abortive ternary complexes, as suggested by the product-inhibition studies. The significance and the interrelationship of duck epsilon-crystallin with other well-known LDHs are discussed with special regard to its role as a structural protein with some enzymic function in lens metabolism.

show abstract

Biochemical comparison of γ‐crystallins from duck and frog eye lenses

Cited by 21 publications

References 13 publications

Crystallin distribution patterns in Litoria infrafrenata and Phyllomedusa sauvagei lenses

Crystallin distribution patterns in Litoria infrafrenata and Phyllomedusa sauvagei lenses

Crystallin distribution patterns in concentric layers from toad eye lenses

Kinetic analysis of duck ε-crystallin, a lens structural protein with lactate dehydrogenase activity

Contact Info

Product

Resources

About