s are required for pectin methyl-esterification and mucilage release in seed coat epidermal cells.

Introduction: play a role in the methylation of polysaccharides synthesized by the Golgi. Pectin homogalacturonan (HG) methyl-esterification is essential for the proper function of this polysaccharide in cell walls. In order to better understand the role of in HG biosynthesis, we analyzed mucilage methyl-esterification in mutants.

Eudicot primary cell wall glucomannan is related in synthesis, structure, and function to xyloglucan.

Hemicellulose polysaccharides influence assembly and properties of the plant primary cell wall (PCW), perhaps by interacting with cellulose to affect the deposition and bundling of cellulose fibrils. However, the functional differences between plant cell wall hemicelluloses such as glucomannan, xylan, and xyloglucan (XyG) remain unclear. As the most abundant hemicellulose, XyG is considered important in eudicot PCWs, but plants devoid of XyG show relatively mild phenotypes.

Golgi-localized putative S-adenosyl methionine transporters required for plant cell wall polysaccharide methylation.

Polysaccharide methylation, especially that of pectin, is a common and important feature of land plant cell walls. Polysaccharide methylation takes place in the Golgi apparatus and therefore relies on the import of S-adenosyl methionine (SAM) from the cytosol into the Golgi. However, so far, no Golgi SAM transporter has been identified in plants.

Two conifer GUX clades are responsible for distinct glucuronic acid patterns on xylan.

Wood of coniferous trees (softwood), is a globally significant carbon sink and an important source of biomass. Despite that, little is known about the genetic basis of softwood cell wall biosynthesis. Branching of xylan, one of the main hemicelluloses in softwood secondary cell walls, with glucuronic acid (GlcA) is critical for biomass recalcitrance.

Loss of TaIRX9b gene function in wheat decreases chain length and amount of arabinoxylan in grain but increases cross-linking.

Wheat contains abundant xylan in cell walls of all tissues, but in endosperm, there is an unusual form of xylan substituted only by arabinose (arabinoxylan; AX) that has long chains and low levels of feruloylation, a fraction of which is extractable in water (WE-AX). WE-AX acts as soluble dietary fibre but also gives rise to viscous extracts from grain, a detrimental trait for some non-food uses of wheat. Here, we show that a glycosyl transferase family 43 wheat gene abundantly expressed in endosperm complements the Arabidopsis irx9 mutant and so name the three homoeologous genes TaIRX9b.

Two members of the DUF579 family are responsible for arabinogalactan methylation in Arabidopsis.

All members of the DUF579 family characterized so far have been described to affect the integrity of the hemicellulosic cell wall component xylan: GXMs are glucuronoxylan methyltransferases catalyzing 4-O-methylation of glucuronic acid on xylan; IRX15 and IRX15L, although their enzymatic activity is unknown, are required for xylan biosynthesis and/or xylan deposition. Here we show that the DUF579 family members, AGM1 and AGM2, are required for 4-O-methylation of glucuronic acid of a different plant cell wall component, the highly glycosylated arabinogalactan proteins (AGPs).

New steps in mucilage biosynthesis revealed by analysis of the transcriptome of the UDP-rhamnose/UDP-galactose transporter 2 mutant.

Upon imbibition, epidermal cells of Arabidopsis thaliana seeds release a mucilage formed mostly by pectic polysaccharides. The Arabidopsis mucilage is composed mainly of unbranched rhamnogalacturonan-I (RG-I), with low amounts of cellulose, homogalacturonan, and traces of xylan, xyloglucan, galactoglucomannan, and galactan. The pectin-rich composition of the mucilage and their simple extractability makes this structure a good candidate to study the biosynthesis of pectic polysaccharides and their modification.

UUAT1 Is a Golgi-Localized UDP-Uronic Acid Transporter That Modulates the Polysaccharide Composition of Arabidopsis Seed Mucilage.

UDP-glucuronic acid (UDP-GlcA) is the precursor of many plant cell wall polysaccharides and is required for production of seed mucilage. Following synthesis in the cytosol, it is transported into the lumen of the Golgi apparatus, where it is converted to UDP-galacturonic acid (UDP-GalA), UDP-arabinose, and UDP-xylose. To identify the Golgi-localized UDP-GlcA transporter, we screened mutants in genes coding for putative nucleotide sugar transporters for altered seed mucilage, a structure rich in the GalA-containing polysaccharide rhamnogalacturonan I.

LGBT Coverage in U.S. Dental Schools and Dental Hygiene Programs: Results of a National Survey.

The aims of this study were to assess curricular coverage of lesbian, gay, bisexual, and transgender (LGBT) content in U.S. and Canadian dental schools and U.

The inside and outside: topological issues in plant cell wall biosynthesis and the roles of nucleotide sugar transporters.

The cell wall is a complex extracellular matrix composed primarily of polysaccharides. Noncellulosic polysaccharides, glycoproteins and proteoglycans are synthesized in the Golgi apparatus by glycosyltransferases (GTs), which use nucleotide sugars as donors to glycosylate nascent glycan and glycoprotein acceptors that are subsequently exported to the extracellular space. Many nucleotide sugars are synthesized in the cytosol, leading to a topological issue because the active sites of most GTs are located in the Golgi lumen.

The Golgi localized bifunctional UDP-rhamnose/UDP-galactose transporter family of Arabidopsis.

Plant cells are surrounded by a cell wall that plays a key role in plant growth, structural integrity, and defense. The cell wall is a complex and diverse structure that is mainly composed of polysaccharides. The majority of noncellulosic cell wall polysaccharides are produced in the Golgi apparatus from nucleotide sugars that are predominantly synthesized in the cytosol.

Lesbian, gay, bisexual, and transgender (LGBT) issues in dental school environments: dental student leaders' perceptions.

The objectives of the study reported in this article were to assess dental student leaders' perceptions of educational efforts concerning lesbian, gay, bisexual, and transgender (LGBT) topics and the cultural climate concerning LGBT issues in dental schools in the United States and Canada. In addition, the perceptions of student leaders who self-identified as belonging to the LGBT community and of students with a heterosexual orientation were compared. Data were collected from 113 dental student leaders from twenty-seven dental schools in the United States and three in Canada.

Accuracy and consistency of radiographic interpretation among clinical instructors in conjunction with a training program.

There are inaccuracies and inconsistencies of radiographic interpretation among clinical instructors. The purpose of this investigation was to determine if a training program could improve the accuracy and consistency of instructors' ratings of bone loss. A total of thirty-five clinical instructors consisting of periodontal faculty (periodontists and general dentists), dental hygiene faculty, and periodontal graduate students viewed projected digitized radiographic images and quantified bone loss for twenty-five teeth into four descriptive categories.

Accuracy and consistency of radiographic interpretation among clinical instructors using two viewing systems.

Accurate and consistent radiographic interpretation among clinical instructors is needed for assessment of teaching, student performance, and patient care. The purpose of this investigation was to determine if the method of radiographic viewing affects accuracy and consistency of instructors' determinations of bone loss. Forty-one clinicians who provide instruction in a dental school clinical teaching program (including periodontists, general dentists, periodontal graduate students, and dental hygienists) quantified bone loss for up to twenty-five teeth into four descriptive categories using a view box for plain film viewing or a projection system for digitized image viewing.