Transcriptional and biochemical analyses of gibberellin expression and content in germinated barley grain.

Mobilization of reserves in germinated cereal grains is critical for early seedling vigour, global crop productivity, and hence food security. Gibberellins (GAs) are central to this process. We have developed a spatio-temporal model that describes the multifaceted mechanisms of GA regulation in germinated barley grain.

A Novel (1,4)-β-Linked Glucoxylan Is Synthesized by Members of the Gene Family in Land Plants.

As a significant component of monocot cell walls, (1,3;1,4)-β-glucan has conclusively been shown to be synthesized by the cellulose synthase-like F6 protein. In this study, we investigated the synthetic activity of other members of the barley () gene family using heterologous expression. As expected, the majority of the genes encode proteins that are capable of synthesizing detectable levels of (1,3;1,4)-β-glucan.

Mitochondrial function modulates touch signalling in Arabidopsis thaliana.

Plants respond to short- and long-term mechanical stimuli, via altered transcript abundance and growth respectively. Jasmonate, gibberellic acid and calcium have been implicated in mediating responses to mechanical stimuli. Previously it has been shown that the transcript abundance for the outer mitochondrial membrane protein of 66 kDa (OM66), is induced several fold after 30 min in response to touch.

Racemization at the Asp 58 residue in αA-crystallin from the lens of high myopic cataract patients.

Post-translational modifications in lens proteins are key causal factors in cataract. As the most abundant post-translational modification in the lens, racemization may be closely related to the pathogenesis of cataract. Racemization of αA-crystallin, a crucial structural and heat shock protein in the human lens, could significantly influence its structure and function.

Adhesion of the posterior capsule to different intraocular lenses following cataract surgery.

Purpose: To investigate the prevalence and morphologic and clinical features of posterior capsule-optic inadhesion following cataract surgery.

Methods: In this prospective cohort study, we examined 518 consecutive patients who had undergone uneventful phacoemulsification and posterior chamber intraocular lens (IOL) implantation. They were assigned into five groups based on the type of IOL used: MC X11 ASP, Rayner 920H A, ZCB00, SN60WF and KS-3Ai.

Interconversion of the peptide isoforms of aspartate: stability of isoaspartates.

A common modification of human long-lived proteins is spontaneous isomerisation of aspartate residues, and its biological importance can be inferred from the ubiquitous presence of protein isoaspartate methyl transferase (PIMT), that repairs this damage. Cyclisation of L-Asp residues yields four isomers: L-Asp, L-isoAsp, D-Asp and D-isoAsp, however little is known about their rate of formation or interconversion. This is important because PIMT is inactive towards D-isoAsp.

Accelerated aging of Asp 58 in αA crystallin and human cataract formation.

Racemisation of amino acids is one of the most abundant modifications in long-lived proteins. In this study racemisation of Asp 58 in the small heat shock protein, αA crystallin, was investigated. In normal human lenses, levels of l-isoAsp, d-isoAsp and d-Asp increased with age, such that by age 70 they accounted for approximately half of the total Asp at this site.

Age-dependent racemization of serine residues in a human chaperone protein.

Racemization is one of the most abundant modifications in long-lived proteins. It has been proposed that the accumulation of such modifications over time could lead to changes in tissues and ultimately human age-related diseases. Serine is one of the main amino acids involved in racemization; however, the site of D-Ser in any aged protein has yet to be reported.

Age-dependent deamidation of glutamine residues in human γS crystallin: deamidation and unstructured regions.

Human aging is associated with the deterioration of long-lived proteins. Gradual cumulative modifications to the life-long proteins of the lens may ultimately be responsible for the pronounced alterations to the optical and physical properties that characterize lenses from older people. γS crystallin, a major human lens protein, is known to undergo several age-dependent changes.

Is protein methylation in the human lens a result of non-enzymatic methylation by S-adenosylmethionine?

Since crystallins in the human lens do not turnover, they are susceptible to modification by reactive molecules over time. Methylation is a major post-translational lens modification, however the source of the methyl group is not known and the extent of modification across all crystallins has yet to be determined. Sites of methylation in human lens proteins were determined using HPLC/mass spectrometry following digestion with trypsin.

Racemization of two proteins over our lifespan: deamidation of asparagine 76 in γS crystallin is greater in cataract than in normal lenses across the age range.

Purpose: Long-lived proteins are widespread in man, yet little is known about the processes that affect their function over time, or their role in age-related diseases.

Methods: Racemization of two proteins from normal and cataract human lenses were compared with age using tryptic digestion and LC/mass spectrometry. Asp 151 in αA crystallin and Asn 76 in γS crystallin were studied.

Racemisation and human cataract. D-Ser, D-Asp/Asn and D-Thr are higher in the lifelong proteins of cataract lenses than in age-matched normal lenses.

ASTRACT: Several amino acids were found to undergo progressive age-dependent racemisation in the lifelong proteins of normal human lenses. The two most highly racemised were Ser and Asx. By age 70, 4.

Novel breast cancer biomarkers identified by integrative proteomic and gene expression mapping.

Proteomic and transcriptomic platforms both play important roles in cancer research, with differing strengths and limitations. Here, we describe a proteo-transcriptomic integrative strategy for discovering novel cancer biomarkers, combining the direct visualization of differentially expressed proteins with the high-throughput scale of gene expression profiling. Using breast cancer as a case example, we generated comprehensive two-dimensional electrophoresis (2DE)/mass spectrometry (MS) proteomic maps of cancer (MCF-7 and HCC-38) and control (CCD-1059Sk) cell lines, identifying 1724 expressed protein spots representing 484 different protein species.

Quantitative profiling of drug-associated proteomic alterations by combined 2-nitrobenzenesulfenyl chloride (NBS) isotope labeling and 2DE/MS identification.

The identification of drug-responsive biomarkers in complex protein mixtures is an important goal of quantitative proteomics. Here, we describe a novel approach for identifying such drug-induced protein alterations, which combines 2-nitrobenzenesulfenyl chloride (NBS) tryptophan labeling with two-dimensional gel electrophoresis (2DE)/mass spectrometry (MS). Lysates from drug-treated and control samples are labeled with light or heavy NBS moiety and separated on a common 2DE gel, and protein alterations are identified by MS through the differential intensity of paired NBS peptide peaks.