Exemplifying practice-based research: the influence of age on myopia progression.

CLINICAL RELEVANCE: The electronic storage of patient records and modern-day search engines present private practitioners with a unique opportunity to extract valuable data for investigative research purposes. However, practitioners seldom harness this resource and consequently a vast repository of clinical data remains largely unexplored. BACKGROUND: This study, based on real-world data from an optometric practice, stands as an example of how clinicians can actively contribute to research. In doing so it underscores the role played by age in determining the rate of natural myopia progression. METHODS: A retrospective data analysis of the refractive status, age and optical correction type of participants, was conducted over six years. Forty-four participants were recruited (25 contact lens and 19 spectacle wearers), with a presenting age varying from 5 to 20 years (median, 11 years). Non-cycloplegic, monocular foveal refractions were completed using a ShinNippon open-field autorefractor, corroborated with subjective refraction. The mean spherical equivalent refractive error was calculated for the participants' initial visit (baseline measure) and for a six-year follow-up visit (progression measure), with myopia progression defined as the difference between these measures. Statistical analyses were computed using Decision Tree Analysis, with a significance level set at 95%. RESULTS: The participant age at first visit exerted a significant influence on natural myopia progression over the assessment period (F 1,42 = 17.11, p < 0.001). Individuals aged ≤ 10 years had approximately twice the myopic progression (mean, -2.27 D) of those aged > 10 years (mean, -1.13 D). Neither degree of myopia at the initial visit nor optical correction type had a significant effect on progression (p > 0.05). CONCLUSIONS: Utilizing the advantage of small real-world data samples, the benefit of research by private practitioners was demonstrated, providing evidence that the age at which a child first presents for an eye examination is highly influential in determining their rate of myopia progression.

The Differential Contribution of Macular Pigments and Foveal Anatomy to the Perception of Maxwell's Spot and Haidinger's Brushes.

The relationship of macular pigments and foveal anatomy to the perception of Maxwell's spot (MS) and Haidinger's brushes (HB) entoptic phenomena were investigated. Dual-wavelength-autofluorescence and OCT were used to define macular pigment density and foveal anatomy in 52 eyes. MS was generated by alternating unpolarized red/blue and red/green uniform field illumination. HB was generated by alternating the linear polarization axis of a uniform blue field. In Experiment 1, horizontal widths of MS and HB were measured using a micrometer system and compared with macular pigment densities and OCT-defined morphometry. MS radius (mean 1.4°) was significantly less than HB radius (mean 1.6°), with the spatial extent of both phenomena falling between the boundaries of the foveola and foveal pit. Multiple regression showed MS and HB radii to be significantly associated with the macular pigment spatial profile radius. HB radius, but not MS radius, was also significantly associated with foveolar morphometry. Experiment 2 compared perceptual profiles of MS with macular pigment distribution patterns and demonstrated close agreement. The size and appearance of MS is a direct indicator of macular pigment density and distribution. Measures of HB radii are less specific, with dependence on both macular pigment density and foveal structure.

Assessing changes in mood state in university students following short-term study abroad.

Short-term study-abroad (STSA) programs provide a more accessible alternative for students who would otherwise not consider engaging in academic activities overseas. Though improvements in the levels of intercultural sensitivity and general academic aspects attained by STSA programs have been previously examined, much less is known regarding the impact such programs have in the mood of students. Here, we examined changes in mood state associated with participation in an STSA program in a group of Japanese university students. Mood states were assessed using the Profile of Mood States (POMS), the Satisfaction With Life Scale (SWLS), and the Gratitude Questionnaire (GQ-6). Results indicated that the POMS mean scores of Vigor-Activity and SWLS peaked at the time immediately following participation in the STSA program; moreover, the same scores were found to be at comparable levels even one month after the end of the program. These results indicate that participation in STSA programs can positively influence the mood state of university students, suggesting that the benefits associated with participation in such programs extend beyond typically reported improvements in the academic domain.

The Effect of Age-Related Macular Degeneration on Polarization Pattern Perception.

Purpose: The purpose of this study was to determine if a battery of polarization-modulated stimuli, quantified as a single metric, is effective in identifying macular disease in the presence/absence of cataract or pseudophakia. Methods: Using a modified liquid crystal display, polarization pattern perception (PPP) for a formulated battery of geometric and logMAR stimuli was evaluated in participants that had either no eye pathology (healthy participants) or were grouped according to the presence of cataract, pseudophakia, and/or age-related macular degeneration (AMD). PPP was quantified as response frequencies to individual stimuli, and as a novel monocular polarization sensitivity score (Ps) based on perception of the stimulus battery set. Results: Stimulus response frequencies were pattern-dependent and, compared with healthy participants, reduced for cataract and AMD groups but not for subjects with pseudophakia. Compared with healthy eyes (n = 47, median Ps = 17), Ps was significantly reduced by AMD (n = 59, median Ps = 1, P < 0.001) and, to a lesser extent, by cataracts (n = 80, median Ps = 6, P < 0.001). There was no significant difference between Ps for healthy and pseudophakic eyes (n = 47, median Ps = 13, P = 0.323). There was no significant correlation between Ps and logMAR visual acuity. Conclusions: In the absence of significant cataract, or in pseudophakia, a set of polarization-modulated visual stimuli, quantified as the Ps score, distinguishes AMD from healthy maculae. Translational Relevance: Perception of polarization-modulated stimuli, previously shown to be macula-dependent in a laboratory setting, is effective as a test of macular function in health and disease in a clinic setting.

An Analysis of the Effectiveness of High-level Disinfection for Surgical Instruments Used by Department of Defense Austere Surgical Teams.

INTRODUCTION: The purpose of this investigation was to evaluate the efficacy of currently employed commercial disinfectants in a simulated austere surgical environment similarly faced by ground surgical teams in forward deployed positions. Severe contamination of traumatic combat wounds along with limitations of operations in austere environments may result in available disinfectants providing inadequate surgical instrument decontamination. MATERIALS AND METHODS: The study consisted of nine experimental groups and two control groups evaluating hemostatic forceps found in kits of ground surgical teams. Hemostats were contaminated in a manner replicating the use in austere wartime surgery, cleaned by manual debridement and soaked in a disinfectant. Initially, instruments were debrided in one of three initial liquids (potable water, sterile water, or potable water with Envirocleanse A) and subsequently treated with one of three terminal disinfectants (Cidex OPA, CaviCide, or Neutral Disinfectant Cleaner). Treated hemostats were placed in sterile wire-closure bags for various storage times and tested for viable bacteria measured by colony-forming units. RESULTS: Our findings indicated that mechanical debridement in water, independent of Envirocleanse A, followed by soaking in any of the three terminal disinfectants achieved a marked reduction in recovered bacteria from hemostats regardless of storage length. Of the three disinfectants tested, Cidex OPA appeared to be the most robust in terms of decontamination, followed by CaviCide and Neutral Disinfectant Cleaner. CONCLUSIONS: This study supports the conclusion that all evaluated disinfectants are capable of rapidly producing instruments with minimal bacterial contaminants when standard sterilization is unavailable. Therefore, when lifesaving surgical intervention must be performed in a deployed environment, austere surgical teams can confidently utilize either product with minimal risk of infection. However, of the disinfectants, Cidex OPA appears to be most effective in reducing bacterial contamination for both rapid and slow turnover of instrument usage, and thus, the disinfectants are recommended for application when sterilization is not available.

The Clinical Application of Polarization Pattern Perception.

Purpose: Determine the repeatability of and optimum stimulus parameters for testing polarization pattern perception in a real-world clinical population, and assess the ability of polarization perception to distinguish normal from abnormal eyes. Methods: Polarization perception was evaluated in staff and patients attending ophthalmology clinics at Warwick Hospital, UK. A series of visual stimuli were presented in pseudorandom order using a liquid-crystal-display-based polarization pattern generator. Stimuli included geometric patterns, gratings, checkerboards, and optotypes. Participants had one or both eyes diagnosed as normal or abnormal following ophthalmic examination, optical coherence tomography, and measures of visual acuity. Measurement scores were assigned to the eye(s) of each participant depending on the total number of stimuli perceived or identified. Results: Stimuli covered the range of spatial scales resolvable within polarization perception by normal and abnormal eyes. Different stimuli had different saliencies. For each stimulus type, polarization perception in the abnormal group was significantly reduced compared with normal eyes (P < 0.001). Relative stimulus salience was broadly similar for normal-eye and abnormal-eye viewing groups, being greatest for radially symmetric patterns and least for optotypes. Checkerboard pattern salience had an inverse logarithmic relationship with check fundamental spatial frequency. A devised metric covering the dynamic range of polarization perception was repeatable, and the score derived from the metric was reduced in the abnormal group compared with the normal group (P < 0.001). Conclusions: Clinically useful metrics of polarization perception distinguish between normal and abnormal eyes. Translational Relevance: Perception of spatial patterns formed of non-uniform polarization fields has potential as a quantitative clinical diagnostic measurement.

mRNA adenosine methylase (MTA) deposits m6A on pri-miRNAs to modulate miRNA biogenesis in Arabidopsis thaliana.

In Arabidopsis thaliana, the METTL3 homolog, mRNA adenosine methylase (MTA) introduces N6-methyladenosine (m6A) into various coding and noncoding RNAs of the plant transcriptome. Here, we show that an MTA-deficient mutant (mta) has decreased levels of microRNAs (miRNAs) but accumulates primary miRNA transcripts (pri-miRNAs). Moreover, pri-miRNAs are methylated by MTA, and RNA structure probing analysis reveals a decrease in secondary structure within stem-loop regions of these transcripts in mta mutant plants. We demonstrate interaction between MTA and both RNA Polymerase II and TOUGH (TGH), a plant protein needed for early steps of miRNA biogenesis. Both MTA and TGH are necessary for efficient colocalization of the Microprocessor components Dicer-like 1 (DCL1) and Hyponastic Leaves 1 (HYL1) with RNA Polymerase II. We propose that secondary structure of miRNA precursors induced by their MTA-dependent m6A methylation status, together with direct interactions between MTA and TGH, influence the recruitment of Microprocessor to plant pri-miRNAs. Therefore, the lack of MTA in mta mutant plants disturbs pri-miRNA processing and leads to the decrease in miRNA accumulation. Furthermore, our findings reveal that reduced miR393b levels likely contributes to the impaired auxin response phenotypes of mta mutant plants.

The electrophysiological response to polarization-modulated patterned visual stimuli.

Recent reports indicate that the subjective ability of humans to discriminate between polarization E-vector orientations approaches that of many invertebrates. Here, we show that polarization-modulated patterned stimuli generate an objectively recordable electrophysiological response in humans with normal vision. We investigated visual evoked potential (VEP) and electroretinographic (ERG) responses to checkerboard patterns defined solely by their polarization E-vector orientation alternating between ± 45°. Correcting for multiple comparisons, paired-samples t-tests were conducted to assess the significance of post-stimulus deflections from baseline measures of noise. Using standard check pattern sizes for clinical electrophysiology, and a pattern-reversal protocol, participants showed a VEP response to polarization-modulated patterns (PolVEP) with a prominent and consistent positive component near 150 ms (p < 0.01), followed by more variable negative components near 200 ms and 300 ms. The effect was unrecordable with visible wavelengths >550 nm. Further, pseudo-depolarization negated the responses, while control studies provided confirmatory evidence that the PolVEP response was not the product of luminance artefacts. Polarization-modulated patterns did not elicit a recordable ERG response. The possible origins of the PolVEP signals, and the absence of recordable ERG signals, are discussed. We conclude that evoked cortical responses to polarization-modulated patterns provide an objective measure of foveal function, suitable for both humans and non-human primates with equivalent macular anatomy.

Polarization perception in humans: on the origin of and relationship between Maxwell's spot and Haidinger's brushes.

Under specific conditions of illumination and polarization, differential absorption of light by macular pigments is perceived as the entoptic phenomena of Maxwell's spot (MS) or Haidinger's brushes (HB). To simulate MS and HB, an existing computational model of polarization-dependent properties of the human macula was extended by incorporating neuronal adaptation to stabilized retinal images. The model predicted that polarized light modifies the appearance of MS leading to the perception of a novel phenomenon. The model also predicted a correlation between the observed diameters of MS and HB. Predictions were tested psychophysically in human observers, whose measured differences in the diameters of each entoptic phenomenon generated with depolarized and linearly polarized light were consistent with the model simulations. These findings support a common origin of each phenomenon, and are relevant to the clinical use of polarization stimuli in detecting and monitoring human eye disorders, including macular degeneration. We conclude: (i) MS and HB both result from differential light absorption through a radial diattenuator, compatible with the arrangement of macular pigments in Henle fibres; (ii) the morphology of MS is dependent on the degree of linear polarization; (iii) perceptual differences between MS and HB result from different states of neural adaptation.

Increased Word Spacing Improves Performance for Reading Scrolling Text with Central Vision Loss.

SIGNIFICANCE: Scrolling text can be an effective reading aid for those with central vision loss. Our results suggest that increased interword spacing with scrolling text may further improve the reading experience of this population. This conclusion may be of particular interest to low-vision aid developers and visual rehabilitation practitioners. PURPOSE: The dynamic, horizontally scrolling text format has been shown to improve reading performance in individuals with central visual loss. Here, we sought to determine whether reading performance with scrolling text can be further improved by modulating interword spacing to reduce the effects of visual crowding, a factor known to impact negatively on reading with peripheral vision. METHODS: The effects of interword spacing on reading performance (accuracy, memory recall, and speed) were assessed for eccentrically viewed single sentences of scrolling text. Separate experiments were used to determine whether performance measures were affected by any confound between interword spacing and text presentation rate in words per minute. Normally sighted participants were included, with a central vision loss implemented using a gaze-contingent scotoma of 8° diameter. In both experiments, participants read sentences that were presented with an interword spacing of one, two, or three characters. RESULTS: Reading accuracy and memory recall were significantly enhanced with triple-character interword spacing (both measures, P ≤ .01). These basic findings were independent of the text presentation rate (in words per minute). CONCLUSIONS: We attribute the improvements in reading performance with increased interword spacing to a reduction in the deleterious effects of visual crowding. We conclude that increased interword spacing may enhance reading experience and ability when using horizontally scrolling text with a central vision loss.

Computational simulation of human perception of spatially dependent patterns modulated by degree and angle of linear polarization.

Recent studies on polarization perception have shown that humans are sensitive to patterned stimuli modulated by either angle of linear polarization (AoP) or degree of polarization (DoP). Here, we present a model of human polarization sensitivity that incorporates both AoP and DoP as spatially dependent input variables. Applying the model to both sinusoidal- and square-wave-modulated DoP and AoP inputs, we demonstrate the theoretical similarities and differences generated by such inputs. Our model indicates the following: (i) edge boundaries between two adjacent areas of different linear polarization are preserved for both AoP- and DoP-modulated stimuli; and (ii) compared with DoP stimuli, AoP stimuli generate greater luminance changes at the photoreceptor level, suggesting that AoP-modulated patterns are potentially more salient than DoP patterns. The computational model is supported experimentally with an optical test of the model comprising a radial diattenuating polarizing filter and modified liquid crystal displays generating DoP- and AoP-modulated outputs. Psychophysical measures of human sensitivity confirm the increased salience of AoP- relative to DoP-modulated stimuli. These findings have practical application to the selection of DoP- and AoP-modulated stimuli for the investigation of macular function and macular pigment density in healthy and diseased eyes.

N6-Methyladenosine Inhibits Local Ribonucleolytic Cleavage to Stabilize mRNAs in Arabidopsis.

N6-methyladenosine (m6A) is a dynamic, reversible, covalently modified ribonucleotide that occurs predominantly toward 3' ends of eukaryotic mRNAs and is essential for their proper function and regulation. In Arabidopsis thaliana, many RNAs contain at least one m6A site, yet the transcriptome-wide function of m6A remains mostly unknown. Here, we show that many m6A-modified mRNAs in Arabidopsis have reduced abundance in the absence of this mark. The decrease in abundance is due to transcript destabilization caused by cleavage occurring 4 or 5 nt directly upstream of unmodified m6A sites. Importantly, we also find that, upon agriculturally relevant salt treatment, m6A is dynamically deposited on and stabilizes transcripts encoding proteins required for salt and osmotic stress response. Overall, our findings reveal that m6A generally acts as a stabilizing mark through inhibition of site-specific cleavage in plant transcriptomes, and this mechanism is required for proper regulation of the salt-stress-responsive transcriptome.

Computational simulation of Haidinger's brushes.

Haidinger's brushes (HB) are entoptic phenomena resulting from differential absorption of linear polarized light by the human macula. Computational models have assisted in understanding the behavior of these subjective phenomena but have been limited in their application. This study presents a revised computational model that incorporates known determinants of the form and behavior of HB. The model generates both static and animated simulations of HB that can be quantified by their density, contrast, and radial/circumferential extent. Measured physiological parameters are used to demonstrate the dependency of HB on macular pigment (MP) density, MP distribution, and ocular retardation. Physiological variations in these parameters explain the reported variations in the perception of HB.

The nucleotides they are a-changin': function of RNA binding proteins in post-transcriptional messenger RNA editing and modification in Arabidopsis.

During and after transcription, the fate of an RNA molecule is almost entirely directed by the cohorts of interacting RNA-binding proteins (RBPs). RBPs regulate all stages of the life cycle of a messenger RNA (mRNA) molecule, including splicing, polyadenylation, transport out of the nucleus, RNA stability, and translation. In addition to these functions, RBPs can function to modify or edit the sequences encoded by the RNA. While the sequence for each transcript is determined in the genome, by the time an RNA reaches its final fate, the sequence may have been edited, where one nucleotide is converted to another, or modified, where a chemical group, or sometimes others moieties, are covalently linked to a nucleotide base. These changes to the RNA sequence have major consequences on the function of the RNA. Additionally, variation in the levels of the RBPs that perform the editing or modification can drastically affect the fitness of an organism. Here, we review RBPs that are known to edit or modify RNA ribonucleotides, focusing on the RNA editing ability of the pentatricopeptide repeat (PPR) proteins and the RBPs that modify adenosine to N6- methyladenosine.

Nuclear m6A reader YTHDC1 regulates alternative polyadenylation and splicing during mouse oocyte development.

The N6-methyladenosine (m6A) modification is the most prevalent internal RNA modification in eukaryotes. The majority of m6A sites are found in the last exon and 3' UTRs. Here we show that the nuclear m6A reader YTHDC1 is essential for embryo viability and germline development in mouse. Specifically, YTHDC1 is required for spermatogonial development in males and for oocyte growth and maturation in females; Ythdc1-deficient oocytes are blocked at the primary follicle stage. Strikingly, loss of YTHDC1 leads to extensive alternative polyadenylation in oocytes, altering 3' UTR length. Furthermore, YTHDC1 deficiency causes massive alternative splicing defects in oocytes. The majority of splicing defects in mutant oocytes are rescued by introducing wild-type, but not m6A-binding-deficient, YTHDC1. YTHDC1 is associated with the pre-mRNA 3' end processing factors CPSF6, SRSF3, and SRSF7. Thus, YTHDC1 plays a critical role in processing of pre-mRNA transcripts in the oocyte nucleus and may have similar non-redundant roles throughout fetal development.

The effect of mood state on visual search times for detecting a target in noise: An application of smartphone technology.

The study of visual perception has largely been completed without regard to the influence that an individual's emotional status may have on their performance in visual tasks. However, there is a growing body of evidence to suggest that mood may affect not only creative abilities and interpersonal skills but also the capacity to perform low-level cognitive tasks. Here, we sought to determine whether rudimentary visual search processes are similarly affected by emotion. Specifically, we examined whether an individual's perceived happiness level affects their ability to detect a target in noise. To do so, we employed pop-out and serial visual search paradigms, implemented using a novel smartphone application that allowed search times and self-rated levels of happiness to be recorded throughout each twenty-four-hour period for two weeks. This experience sampling protocol circumvented the need to alter mood artificially with laboratory-based induction methods. Using our smartphone application, we were able to replicate the classic visual search findings, whereby pop-out search times remained largely unaffected by the number of distractors whereas serial search times increased with increasing number of distractors. While pop-out search times were unaffected by happiness level, serial search times with the maximum numbers of distractors (n = 30) were significantly faster for high happiness levels than low happiness levels (p = 0.02). Our results demonstrate the utility of smartphone applications in assessing ecologically valid measures of human visual performance. We discuss the significance of our findings for the assessment of basic visual functions using search time measures, and for our ability to search effectively for targets in real world settings.

The Effects of Severe Myopia on the Properties of Sampling Units in Peripheral Retina.

SIGNIFICANCE: Poor peripheral visual acuity in myopia may reflect, in part, photoreceptor misalignment with the exit pupil of the eye. We speculate that if such misalignment causes sufficient visual deprivation and/or disrupts retinal feedback processes, it may influence eye growth itself. PURPOSE: It is known that myopic eyes have a reduced peripheral resolution acuity relative to emmetropic eyes, though it remains unclear how mechanical stretching of the retina in myopia impacts on peripheral visual performance. Our aim was to determine how retinal stretching affects the properties of sampling units in peripheral vision. METHODS: Three-dimensional magnetic resonance imaging provided a depiction in vivo of ocular shape, allowing the inter-eye ratio of retinal image surface areas and the relative alignment of surfaces to be determined in our observer, who was unique in having severe myopia in the right eye (~21 D) but only modest myopia in the left (~3 D). Visual performance was assessed for the detection and direction discrimination of drifting sinusoids positioned 40° in the temporal retina. Applying the sampling theorem to our measures, we estimated the density and cut-off frequency of the underlying sampling units. RESULTS: The retinal image surface area of the right eye was 40% larger than that of the left and was rotated 8.9° anticlockwise relative to the left eye's image surface. In agreement with a linear stretch model of myopia, the sampling density of the right eye was reduced by approximately the same ratio as that predicted from the inter-eye MRI data, namely, 1.18. However, the cut-off frequency (cycles/mm) of the right eye was approximately half that of the left, a reduction that cannot be explained solely by a linear areal expansion of retinal sampling units. CONCLUSIONS: Poor peripheral acuity in severe myopia may be caused, at least in part, by receptoral misalignment with the exit pupil.

Word Mode: a crowding-free reading protocol for individuals with macular disease.

Central retinal loss through macular disease markedly reduces the ability to read largely because identification of a word using peripheral vision is negatively influenced by nearby text, a phenomenon termed visual crowding. Here, we present a novel peripheral reading protocol, termed Word Mode, that eliminates crowding by presenting each word in isolation but in a position that mimics its natural position in the line of text being read, with each new word elicited using a self-paced button press. We used a gaze-contingent paradigm to simulate a central scotoma in four normally-sighted observers, and measured oral reading speed for text positioned 7.5° in the inferior field. Compared with reading whole sentences, our crowding-free protocol increased peripheral reading speeds by up to a factor of seven, resulted in significantly fewer reading errors and fixations per sentence, and reduced both the critical print size and the text size required for spot reading by 0.2-0.3 logMAR. We conclude that the level of reading efficiency afforded by the crowding-free reading protocol Word Mode may return reading as a viable activity to many individuals with macular disease.

The spectral, spatial and contrast sensitivity of human polarization pattern perception.

It is generally believed that humans perceive linear polarized light following its conversion into a luminance signal by diattenuating macular structures. Measures of polarization sensitivity may therefore allow a targeted assessment of macular function. Our aim here was to quantify psychophysical characteristics of human polarization perception using grating and optotype stimuli defined solely by their state of linear polarization. We show: (i) sensitivity to polarization patterns follows the spectral sensitivity of macular pigment; (ii) the change in sensitivity across the central field follows macular pigment density; (iii) polarization patterns are identifiable across a range of contrasts and scales, and can be resolved with an acuity of 15.4 cycles/degree (0.29 logMAR); and (iv) the human eye can discriminate between areas of linear polarization differing in electric field vector orientation by as little as 4.4°. These findings, which support the macular diattenuator model of polarization sensitivity, are unique for vertebrates and approach those of some invertebrates with a well-developed polarization sense. We conclude that this sensory modality extends beyond Haidinger's brushes to the recognition of quantifiable spatial polarization-modulated patterns. Furthermore, the macular origin and sensitivity of human polarization pattern perception makes it potentially suitable for the detection and quantification of macular dysfunction.

Genome-Wide Mapping of Uncapped and Cleaved Transcripts Reveals a Role for the Nuclear mRNA Cap-Binding Complex in Cotranslational RNA Decay in Arabidopsis.

RNA turnover is necessary for controlling proper mRNA levels posttranscriptionally. In general, RNA degradation is via exoribonucleases that degrade RNA either from the 5' end to the 3' end, such as XRN4, or in the opposite direction by the multisubunit exosome complex. Here, we use genome-wide mapping of uncapped and cleaved transcripts to reveal the global landscape of cotranslational mRNA decay in the Arabidopsis thaliana transcriptome. We found that this process leaves a clear three nucleotide periodicity in open reading frames. This pattern of cotranslational degradation is especially evident near the ends of open reading frames, where we observe accumulation of cleavage events focused 16 to 17 nucleotides upstream of the stop codon because of ribosomal pausing during translation termination. Following treatment of Arabidopsis plants with the translation inhibitor cycloheximide, cleavage events accumulate 13 to 14 nucleotides upstream of the start codon where initiating ribosomes have been stalled with these sequences in their P site. Further analysis in xrn4 mutant plants indicates that cotranslational RNA decay is XRN4 dependent. Additionally, studies in plants lacking CAP BINDING PROTEIN80/ABA HYPERSENSITIVE1, the largest subunit of the nuclear mRNA cap binding complex, reveal a role for this protein in cotranslational decay. In total, our results demonstrate the global prevalence and features of cotranslational RNA decay in a plant transcriptome.