PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Prolamins”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1987

[Comparative study of partial amino acid sequences of prolamins and glutelins from various cereals. VII. Amino acid sequences of prolamin peptides].

The peptide fractions isolated from chymotryptic hydrolysates of wheat, rye and barley prolamines [this journal (1984) 178:173] were separated into pure peptides by high-performance liquid chromatography on octadecyl silica gel. The peptides which were most abundant were analyzed for amino acid composition and in part for amino acid sequence. Besides peptides which are typical for only one of the cereals investigated, peptides of similar composition were found in all three prolamines. These contain repeating sequences and are built up of mainly Gln (Q), Pro (P) and hydrophobic amino acids (X) such as Phe, Tyr, Ile, Val and Leu. One of the most frequent partial sequences is QQPQQPXP.

Amino Acid Sequence↗
PubMed1990

Cloning and characterization of a cDNA encoding a rice 13 kDa prolamin.

A cDNA library constructed from mRNAs obtained from developing rice endosperm was screened with a cDNA clone (lambda RM7) of highest frequency of occurrence (1.8%). The translation product directed by the mRNA which was hybrid-released from lambda RM7 cDNA in a wheat germ cell-free system showed a molecular size of 13 kDa when coexisting with the protein body fraction of developing maize endosperm. A polypeptide sequence composed of 156 amino acids was deduced from the nucleotide sequence. By comparison with the 19 N-terminal amino acids obtained from Edman degradation of the isolated rice 13 kDa prolamin fraction, the signal sequence was determined as consisting of 19 amino acids. The deduced polypeptide is rich in hydrophobic amino acids such as Leu and Val, and also in Gln, but lacks Lys. Hence, the amino acid composition is consistent with that of rice 13 kDa prolamin. By homology with previously reported cereal prolamins, only a single octapeptide sequence, Gln-Gln-Gln-Cys-Cys-Gln-Gln-Leu, which was observed in 15 kDa and 27 kDa zein, B- and gamma-hordein, alpha/beta- and gamma-gliadin, and gamma-secalin was conserved in the rice 10 kDa and 13 kDa prolamin. No repetitive sequences and/or sequences homologous to other cereal prolamins, except the above octapeptide, were observed for the mature 13 kDa prolamin polypeptide. The signal sequence region of the 13 kDa prolamin, however, shows homology of more than 65% in both the nucleotide sequence and the amino acid sequence with rice 10 kDa prolamin and maize zein.

Amino Acid Sequence↗
PubMed1988

Two-dimensional electrophoresis of cereal prolamins: applications to biochemical and genetic analyses.

Three complementary two-dimensional systems for the analysis of cereal prolamins are described. These are electrophoresis at pH 3.1 followed by electrophoresis at pH 9.2, isoelectric focusing (IEF) followed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and SDS-PAGE under non-reducing conditions followed by SDS-PAGE with reduction. They together give information on the pIs, Mrs and charge properties of the individual prolamin components, and on their interactions to form oligomers stabilized by inter-chain disulphide bonds. The three systems are then compared for their effectiveness in analysing unreduced prolamin I fractions from wheat and rye, and the IEF/SDS-PAGE system for analysing reduced and pyridylethylated prolamin fractions from all the major cereals. Finally, applications of the systems in biochemical and genetic studies are discussed and illustrated with three examples: analysis of the structural relationships of the S-rich prolamins (B hordeins and gamma-type hordeins) of barley, determination of the interactions of wheat and rye prolamin subunits in a 2RS/2BL translocation line, and the mapping of genes for alpha-type prolamins in the wild grass Haynaldia villosa.

Chromosome Mapping↗
PubMed1982

Cereal prolamin evolution and homology revealed by sequence analysis.

Prolamin mixtures were isolated from oats, rice, normal and high-lysine sorghum, two varieties of pearl millet, two strains of teosinte, and gamma grass and subjected to NH2-terminal amino acid sequence determinations. In each case (except for rice, whose prolamins apparently have blocked or unavailable NH2-terminal residues), primarily a single sequence was observed despite significant heterogeneity, suggesting that prolamin homology in each cereal arose through duplication and mutation of a single ancestral gene. Comparisons were then made to prolamin sequences previously determined for wheat, corn, barley, and rye. Within genera, different varieties or subspecies exhibited few differences, but more distantly related genera, subtribes, and tribes showed increasingly large differences. Within the subfamily Festucoideae, no homology was apparent between prolamins of oats and those of the subtribe Triticinae (including wheat, rye, and barley, for which prolamin homology was previously demonstrated). Within the subfamily Panicoideae, corn was shown to be closely related to teosinte but more distantly to Tripsacum. Sorghum was shown to have diverged less from corn than had millet. These comparisons demonstrate that prolamin sequence analyses can successfully predict and clarify evolutionary relationships of cereals.

Amino Acid Sequence↗
PubMed1988

Nucleotide and primary sequence of a major rice prolamine.

A recombinant cDNA clone encoding a major rice seed storage prolamine was isolated by antibody screening of a cDNA lambda gt 11 library. This clone contained a single open reading frame encoding a putative rice prolamine precursor (Mr 17,300). In contrast to other cereal prolamines, the primary sequence of the rice prolamine was devoid of any major tandem repetitive sequences, a feature prevalent in all cereal prolamines studied to date. No significant homology was detected between the rice prolamine and other cereal prolamines, indicating that the rice gene evolved from unique ancestral DNA segments.

Amino Acid Sequence↗
PubMedDate not supplied

N-terminal sequences of oat avenins compared to other cereal prolamins.

Like the alcohol-soluble seed storage proteins (also called prolamins) of other cereals, avenins, the oat prolamins, are a series of polymorphic molecules belonging to a multigenic family stored within the protein bodies of the starchy endosperm. Nevertheless, they exhibit some pecularities: among the seed storage proteins, their proportion is low compared to prolamins from other cereal species; their net charge is higher; the amount of Gln + Pro only reaches 49 mol%; they are less polymorphic. We have isolated and purified several avenins and sequenced their N-terminal end. The microheterogeneity and the pecularity of avenins are revealed by the comparison of the N-terminal sequences. Like other prolamins, they exhibit tandem repeats; these repetitive peptides are slightly different from those of other prolamins of the Festucoideae, and the repetition begins earlier in the sequence. As for prolamins from other species, their predicted secondary structure reveals successive beta-turns which might be arranged in a pseudo-helix structure.

Amino Acid Sequence↗
PubMed1992

cDNA cloning and gene expression of the major prolamins of rice.

A full-length cDNA (pS 18) encoding the 16 kDa rice prolamin composed of 158 amino acids was sequenced. Analysis of N-terminal amino acid sequence of a major rice prolamin indicated that an 18 amino acid signal peptide was removed from 16 kDa precursor prolamin to form the 14 kDa prolamin during seed development. Synthesis of the 16 kDa precursor prolamin began around 8 days after flowering (DAF), increased remarkably at 8-11 DAF and gradually reached maximum levels with the maturation of rice seeds.

Amino Acid Sequence↗
PubMed1993

Rice prolamine protein body biogenesis: a BiP-mediated process.

Rice prolamines are sequestered within the endoplasmic reticulum (ER) lumen even though they lack a lumenal retention signal. Immunochemical and biochemical data show that BiP, a protein that binds lumenal polypeptides, is localized on the surface of the aggregated prolamine protein bodies (PBs). BiP also forms complexes with nascent chains of prolamines in polyribosomes and with free prolamines with distinct adenosine triphosphate sensitivities. Thus, BiP retains prolamines in the lumen by facilitating their folding and assembly into PBs.

Adenosine Triphosphate↗
PubMed1987

Prevention by mannan and other sugars of in vitro damage of rat fetal small intestine induced by cereal prolamin peptides toxic for human celiac intestine.

Peptic-tryptic-cotazym and peptic-tryptic digests were obtained, simulating in vivo protein digestion, from pure "bread" wheat gliadins and from rye, barley, and oats prolamine and tested on small intestine cultures from fetal rats. When tested at a concentration of 0.1 mg of peptides/ml of culture medium the peptic-tryptic-cotazym and peptic-tryptic digests of gliadin and prolamines were very active in slowing in vitro development of fetal rat intestine and in increasing the occurrence and severity of degenerative changes. The ability of some sugars to interfere with inhibition of fetal intestinal morphogenesis induced by these peptides was also tested. Mannan at a concentration of 0.1 mM was effective in allowing intestinal morphogenesis to take place in the presence of prolamine peptic-tryptic-cotazym and prolamine peptic-tryptic digests of the four toxic cereals. Some oligomers of N-acetyl-glucosamine were also effective in blocking the inhibitory effect of "bread" wheat gliadin peptides. These data are compatible with the hypothesis that some sugars may exert a protective effect on the toxic activity of cereal prolamin peptides on the human celiac intestine.

Animals↗
PubMed1995

Segmental occlusion of the pancreatic duct with prolamine to prevent fistula formation after distal pancreatectomy.

OBJECTIVE: The authors used prolamine (Ethibloc, Ethicon GmBH, Norderstedt, Germany) for segmental obstruction of the pancreatic duct to prevent pancreatic fistula development after distal pancreatectomy combined with total gastrectomy for gastric malignancies. SUMMARY BACKGROUND DATA: Although the initial clinical application of prolamine was pancreatic duct obstruction for patients with pancreatitis and undergoing pancreatic transplantation and pancreaticoduodenectomy for pancreatic cancer, there are no reports on prevention of pancreatic fistula formation after distal pancreatectomy. METHODS: Prolamine (0.2 mL) was injected into the distal segment of the main duct in the remaining pancreata of 51 patients. Small pancreatic ducts on the cut surface, from which prolamine extravasates, were closed by ligation, the main duct was ligated doubly, and the transected pancreatic margin was closed 15 minutes after phenylpropanolamine hydrochloride injection. RESULTS: No patient developed a pancreatic fistula or the complication of arterial bleeding due to prolonged infection. CONCLUSION: Segmental obstruction of the pancreatic duct with prolamine is useful for preventing pancreatic fistula development after distal pancreatectomy.

Amylases↗
PubMed1996

The same nuclear proteins bind to the 5'-flanking regions of genes for the rice seed storage protein: 16 kDa albumin, 13 kDa prolamin and type II glutelin.

Expression of rice seed storage-protein genes is dramatically regulated over a short period of seed maturation. To characterize the expression mechanism of the rice seed storage protein genes, their expression of major storage protein genes (16 kDa albumin, 13 kDa prolamin and type II glutelin) were compared by RNA blot analysis. Their coordinate expression suggests that the transcriptional regulatory machinery is shared among the glutelin, prolamin and albumin-genes. We isolated two novel genomic genes for prolamins (PG5a and PG5b) and obtained the promoter region of the glutelin gene by PCR. The 5'-flanking regions of these three rice seed storage protein genes were found to contain some similar conserved sequences. Nuclear extract partially purified from maturing rice seeds was used for the gel shift assay of the 5' region of the RA gene. We identified two DNA sequences of RA gene which were recognized by independent DNA-binding proteins. The complexes of these DNA sequences and DNA-binding proteins were inhibited by the fragments containing the 5' regions of the prolamin and glutelin genes, suggesting that these three genes share transcription factors.

Albumins↗
PubMed1989

Molecular characterization of an active wheat LMW glutenin gene and its relation to other wheat and barley prolamin genes.

The isolation and characterisation by DNA sequencing of a low molecular weight (LMW) glutenin gene from wheat is described. The deduced protein contains a signal peptide, a central repetitive region rich in proline and glutamine and N and C terminal non-repetitive domains, similar to other prolamins. A detailed comparison of the C terminal domain of 20 prolamin genes enabled us to divide them into 4 families. The LMW glutenin family is distinct from the alpha, beta- and gamma-gliadin families of wheat and is closest to the B hordein genes of barley. This and other comparisons were also used to assess the pattern of genetic variation among prolamin sequences and to provide a molecular basis for the interpretation of prolamin size polymorphism. The 5' flanking fragment of the isolated gene was previously shown to direct endosperm-specific expression of a reporter gene in transgenic tobacco. Evidence is provided that the isolated gene is also active in wheat and its transcription initiation site was determined. Features of the gene which may be relevant to its activity are discussed.

Amino Acid Sequence↗
PubMed1987

Characterization and genetic control of the prolamins of Haynaldia villosa: relationship to cultivated species of the Triticeae (rye, wheat, and barley).

Haynaldia villosa is a wild grass of the tribe Triticeae, other members of which include the cultivated cereals barley, rye, and wheat. We have made an electrophoretic and chemical characterization of the major seed storage proteins (prolamins) of H. villosa and determined the chromosomal locations of the structural genes for some components using the available wheat/H. villosa chromosome addition lines. As in wheat, barley, and rye, groups of high molecular weight (polymeric), sulfur-poor (monomeric), and sulfur-rich (monomeric gamma-type and polymeric) prolamins can be recognized. Most of the components are encoded by genes on chromosome 1 Ha, which is homologous with the chromosomes controlling many of the prolamins in wheat and rye and all of those in barley. In addition, H. villosa also contains alpha-type sulfur-rich prolamins, previously detected only in wheat and its close relatives. These may be encoded by genes on chromosome 6Ha, which is homologous with the group 6 chromosomes that control the alpha-type gliadins of wheat. Despite the proposed close relationship between Haynaldia and ryes, no evidence was found for the presence of proteins closely related to the Mr 75,000 gamma-secalins which are characteristic of wild and cultivated species of Secale.

Chromosome Mapping↗
PubMed1993

The endosperm-specific expression of a rice prolamin chimaeric gene in transgenic tobacco plants.

The 5' upstream region (-680 to +40), containing the potential promoter and complete signal peptide coding sequence of the rice seed storage prolamin gene was amplified in vitro using the polymerase chain reaction from the genome of Chinese rice cultivar Zhonghua 8. The physical map and DNA sequence analysis show strong homology with the 5' flanking region of the rice prolamin gene published by Kim and Okita (1988a). No change in the signal peptide coding sequence and a long leader sequence with several small open reading frames were found. The chimaeric gene containing the 5' flanking region of the prolamin gene (-680 to -18) was transcriptionally fused with the beta-glucuronidase (GUS) reporter gene and the fusion junction was confirmed by both physical mapping and DNA sequence analysis. The resultant chimaeric gene was used to transform tobacco explants, using the Ti binary system of Agrobacterium tumefaciens LBA4404. Three transgenic tobacco plants with as many as 20 copies of the chimaeric GUS gene (confirmed by dot and Southern hybridization) were analysed further. Histochemical analysis revealed GUS activity in the endosperm tissue of tobacco seed at the developmental stage about 20 days after flowering (DAF). No GUS activity was found in leaves, stems, roots and flowers of the transgenic tobacco plants. Therefore, we conclude that the 5' upstream region from -680 to -18 was sufficient to confer the endosperm-specific expression of the rice prolamin gene.

Base Sequence↗
PubMed1993

5'-flanking region responsible for endosperm-specific expression of rice prolamine chimeric gene in transgenic tobacco.

The 5' upstream region (-680-(+)40) containing the complete signal peptide coding sequence of the rice seed storage prolamine gene was amplified in vitro with polymerase chain reaction from the genome of Chinese super rice cultivar Zhonghua 8. Physical map and DNA sequence analysis showed strong homology with the 5'-flanking region of rice prolamine gene reported by Kim in 1988. No changes in the signal peptide coding sequence and a long leader sequence with several small ORFs were found. Chimeric gene containing 5'-flanking region of the prolamine gene has been transcriptionally fused with the beta-glucuronidase reporter gene. The fusion junction was confirmed by both physical map and DNA sequence analysis. The resultant chimeric gene was used to transform the tobacco explants by Ti binary system of Agrobacterium tumefaciens LBA4404. With dot and Southern blotting hybridization, three transgenic tobacco plants with the copies of chimeric GUS genes as many as 20 were obtained. Histochemical analysis revealed that the GUS activity in the endosperm tissues of tobacco seeds at the developmental stage was about 20 DAP. No GUS activity was found in leaves, stems, roots and flowers of the transgenic tobacco plants. Therefore, we concluded that the 5'-upstream cis-elements from -680 to -18 were enough to confer the endosperm-specific and temporal expression of rice prolamine gene.

Base Sequence↗
PubMed1988

Role of pancreatic duct occlusion with prolamine (Ethibloc) in necrotizing pancreatitis.

There is evidence that the pancreatic duct plays an important role in the evolution of necrotizing pancreatitis. We hypothesized that occlusion of the pancreatic duct and its smaller ductules with prolamine (Ethibloc) in opossums at risk of severe necrotizing pancreatitis would have a beneficial effect on the progression of the disease. Sixteen opossums underwent bile duct ligation below the entrance of the pancreatic duct. They were divided into four groups at 6 days. Group I (control, n = 5) opossums were killed for histologic observation of the degree of necrosis of the pancreas; group II (n = 5) underwent external drainage of the pancreatic biliary duct; group III (n = 4) had external biliary drainage and ligation of the pancreatic duct; group IV (n = 7) was treated with external biliary drainage and ligation of the main pancreatic duct after instillation of prolamine. Serum amylase, lipase, and calcium values were determined. The pancreas was examined by inspection and histologically at the time of death, and the severity of the disease was determined by quantitation of pancreatic tissue necrosis. All animals in groups II and III died 8 to 14 days after bile duct ligation, and all had severe necrotizing pancreatitis. All animals in group IV survived and were killed at 2 to 10 weeks after prolamine (Ethibloc) injection into the pancreatic duct. A mild edematous pancreatitis was observed in all seven animals. Prolamine (Ethibloc) provided dramatic protection from progressive necrosis. This study does not provide an explanation, but it allows for speculation that ductal injection interrupted the deleterious effect of proteolytic enzymes and their leakage into the interstitial space of the pancreas.

Amylases↗
PubMed1984

[Parotid duct occlusion with prolamine--sequelae of long-term administration in the animal model].

The effects of occlusion of the parotid excretory duct, after injection of a basic aminoacid solution (prolamine), were studied in 12 rabbit parotid glands one year after prolamine application. 40% of the experimental animals present the picture of an extensive abscess-forming sialadenitis both macroscopically and microscopically. The secretory parenchyma of the gland is almost completely eliminated. Remnants of the injected prolamine solution found in the duct system could possibly be responsible for the abscess formation. At the present experimental stage therapeutic application of prolamine in the human parotid gland cannot be recommended.

Abscess↗