The CELL NUMBER REGULATOR FW2.2 protein regulates cell-to-cell communication in tomato by modulating callose deposition at plasmodesmata.

FW2.2 (standing for FRUIT WEIGHT 2.2), the founding member of the CELL NUMBER REGULATOR (CNR) gene family, was the first cloned gene underlying a quantitative trait locus (QTL) governing fruit size and weight in tomato (Solanum lycopersicum). However, despite this discovery over 20 years ago, the molecular mechanisms by which FW2.2 negatively regulates cell division during fruit growth remain undeciphered. In the present study, we confirmed that FW2.2 is a membrane-anchored protein whose N- and C-terminal ends face the apoplast. We unexpectedly found that FW2.2 is located at plasmodesmata (PD). FW2.2 participates in the spatiotemporal regulation of callose deposition at PD and belongs to a protein complex which encompasses callose synthases. These results suggest that FW2.2 has a regulatory role in cell-to-cell communication by modulating PD transport capacity and trafficking of signaling molecules during fruit development.

Ploidy-specific transcriptomes shed light on the heterogeneous identity and metabolism of developing tomato pericarp cells.

Endoreduplication, during which cells increase their DNA content through successive rounds of full genome replication without cell division, is the major source of endopolyploidy in higher plants. Endoreduplication plays pivotal roles in plant growth and development and is associated with the activation of specific transcriptional programmes that are characteristic of each cell type, thereby defining their identity. In plants, endoreduplication is found in numerous organs and cell types, especially in agronomically valuable ones, such as the fleshy fruit (pericarp) of tomato presenting high ploidy levels. We used the tomato pericarp tissue as a model system to explore the transcriptomes associated with endoreduplication progression during fruit growth. We confirmed that expression globally scales with ploidy level and identified sets of differentially expressed genes presenting only developmental-specific, only ploidy-specific expression patterns or profiles resulting from an additive effect of ploidy and development. When comparing ploidy levels at a specific developmental stage, we found that non-endoreduplicated cells are defined by cell division state and cuticle synthesis while endoreduplicated cells are mainly defined by their metabolic activity changing rapidly over time. By combining this dataset with publicly available spatiotemporal pericarp expression data, we proposed a map describing the distribution of ploidy levels within the pericarp. These transcriptome-based predictions were validated by quantifying ploidy levels within the pericarp tissue. This in situ ploidy quantification revealed the dynamic progression of endoreduplication and its cell layer specificity during early fruit development. In summary, the study sheds light on the complex relationship between endoreduplication, cell differentiation and gene expression patterns in the tomato pericarp.

Endoreduplication in plant organogenesis: a means to boost fruit growth.

Endoreduplication is the major source of somatic endopolyploidy in higher plants, and leads to variation in cell ploidy levels due to iterative rounds of DNA synthesis in the absence of mitosis. Despite its ubiquitous occurrence in many plant organs, tissues, and cells, the physiological meaning of endoreduplication is not fully understood, although several roles during plant development have been proposed, mostly related to cell growth, differentiation, and specialization via transcriptional and metabolic reprogramming. Here, we review recent advances in our knowledge of the molecular mechanisms and cellular characteristics of endoreduplicated cells, and provide an overview of the multi-scale effects of endoreduplication on supporting growth in plant development. In addition, the effects of endoreduplication in fruit development are discussed, since it is highly prominent during fruit organogenesis where it acts as a morphogenetic factor supporting rapid fruit growth, as illustrated by case of the model fleshy fruit, tomato (Solanum lycopersicum).

Solanum lycopersicum CLASS-II KNOX genes regulate fruit anatomy via gibberellin-dependent and independent pathways.

The pericarp is the predominant tissue determining the structural characteristics of most fruits. However, the molecular and genetic mechanisms controlling pericarp development remain only partially understood. Previous studies have identified that CLASS-II KNOX genes regulate fruit size, shape, and maturation in Arabidopsis thaliana and Solanum lycopersicum. Here we characterized the roles of the S. lycopersicum CLASS-II KNOX (TKN-II) genes in pericarp development via a detailed histological, anatomical, and karyotypical analysis of TKN-II gene clade mRNA-knockdown (35S:amiR-TKN-II) fruits. We identify that 35S:amiR-TKN-II pericarps contain more cells around their equatorial perimeter and fewer cell layers than the control. In addition, the cell sizes but not the ploidy levels of these pericarps were dramatically reduced. Further, we demonstrate that fruit shape and pericarp layer number phenotypes of the 35S:amiR-TKN-II fruits can be overridden by the procera mutant, known to induce a constitutive response to the plant hormone gibberellin. However, neither the procera mutation nor exogenous gibberellin application can fully rescue the reduced pericarp width and cell size phenotype of 35S:amiR-TKN-II pericarps. Our findings establish that TKN-II genes regulate tomato fruit anatomy, acting via gibberellin to control fruit shape but utilizing a gibberellin-independent pathway to control the size of pericarp cells.

Asociación entre la infección por virus del papiloma humano y el carcinoma de laringe en adultos de 35-75 años de edad en el instituto nacional del cáncer rosa emilia sánchez pérez de tavarez (incart), en el período agosto 2012 - enero 2019, santo domingo, república dominicana / Association between human papillomavirus infection and laryngeal carcinoma in adults between 35 and 75 years of age at the Rosa Emilia Sánchez Pérez de Tavarez National Cancer Institute (INCART), in the period August 2012 - January 2019, Santo Domingo, Dominican Republic

Introducción: el carcinoma de cabeza y cuello comprende un grupo de neoplasias que comparten un origen anatómico similar. Ocupan el sexto lugar mundial entre las neoplasias de todas las localizaciones, y el sitio afectado con mayor frecuencia es la cavidad oral. Ahora se reconoce el rol del virus del papiloma humano como factor independiente en el desarrollo de estas neoplasias. En los últimos 15 años se ha observado un incremento en la incidencia de carcinoma de células escamosas inducido por virus del papiloma humano (VPH). Materiales y métodos: este es un estudio observacional de tipo descriptivo transversal. Se realizó un análisis documental de los expedientes clínicos de los pacientes que cumplan con los criterios de inclusión. Resultados: en este estudio fue encontrada una prevalencia del 14 % del VPH en cánceres laríngeos. El tipo 16 del VPH fue el único identificado y descrito entre los expedientes clínicos de este estudio y, este último, con una prevalencia de un 20 %. Discusión: el VPH puede estar involucrado en el desarrollo de algunos cánceres de laringe y su rol puede ser más predominante en hombres mayores de 50 años.

Introduction: Head and neck carcinoma comprises a group of neoplasms with similar anatomical origins. They occupy the sixth place in the world among the neoplasias of all the locations, and the most affected site is the oral cavity. The role of the Human Papillomavirus as an independent factor in the development of these neoplasms is now recognized. In the last 15 years, an increase in the incidence of squamous cell carcinoma induced by Human Papillomavirus (HPV) has been observed. Methods: This is an observational study of transversal descriptive type. A documental analysis of the clinical files of the patients that meet the inclusion criteria was performed. Results: in this study, a 14 % prevalence of HPV in laryngeal cancers was found. Type 16 HPV was the only one identified and described in the clinical files of this study and the latter with a prevalence of 20 % Discussion: HPV may be involved in the development of some laryngeal cancers and its role may be more predominant in men older than 50 years.

Zinc Finger-Homeodomain and Mini Zinc Finger proteins are key players in plant growth and responses to environmental stresses.

The ZINC FINGER-HOMEODOMAIN (ZHD) protein family is a plant-specific family of transcription factors containing two conserved motifs: a non-canonical C5H3 zinc finger domain (ZF) and a DNA-binding homeodomain (HD). The MINI ZINC FINGER (MIF) proteins belong to this family, but were possibly derived from the ZHDs by losing the HD. Information regarding the function of ZHD and MIF proteins is scarce. However, different studies have shown that ZHD/MIF proteins play important roles not only in plant growth and development, but also in response to environmental stresses, including drought and pathogen attack. Here we review recent advances relative to ZHD/MIF functions in multiple species, to provide new insights into the diverse roles of these transcription factors in plants. Their mechanism of action in relation to their ability to interact with other proteins and DNA is also discussed. We then propose directions for future studies to understand better their important roles and pinpoint strategies for potential applications in crop improvement.

CIN-like TCP13 is essential for plant growth regulation under dehydration stress.

KEY MESSAGE: A dehydration-inducible Arabidopsis CIN-like TCP gene, TCP13, acts as a key regulator of plant growth in leaves and roots under dehydration stress conditions. Plants modulate their shape and growth in response to environmental stress. However, regulatory mechanisms underlying the changes in shape and growth under environmental stress remain elusive. The CINCINNATA (CIN)-like TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) family of transcription factors (TFs) are key regulators for limiting the growth of leaves through negative effect of auxin response. Here, we report that stress-inducible CIN-like TCP13 plays a key role in inducing morphological changes in leaves and growth regulation in leaves and roots that confer dehydration stress tolerance in Arabidopsis thaliana. Transgenic Arabidopsis plants overexpressing TCP13 (35Spro::TCP13OX) exhibited leaf rolling, and reduced leaf growth under osmotic stress. The 35Spro::TCP13OX transgenic leaves showed decreased water loss from leaves, and enhanced dehydration tolerance compared with their control counterparts. Plants overexpressing a chimeric repressor domain SRDX-fused TCP13 (TCP13pro::TCP13SRDX) showed severely serrated leaves and enhanced root growth. Transcriptome analysis of TCP13pro::TCP13SRDX transgenic plants revealed that TCP13 affects the expression of dehydration- and abscisic acid (ABA)-regulated genes. TCP13 is also required for the expression of dehydration-inducible auxin-regulated genes, INDOLE-3-ACETIC ACID5 (IAA5) and LATERAL ORGAN BOUNDARIES (LOB) DOMAIN 1 (LBD1). Furthermore, tcp13 knockout mutant plants showed ABA-insensitive root growth and reduced dehydration-inducible gene expression. Our findings provide new insight into the molecular mechanism of CIN-like TCP that is involved in both auxin and ABA response under dehydration stress.

SlKIX8 and SlKIX9 are negative regulators of leaf and fruit growth in tomato.

Plant organ size and shape are major agronomic traits that depend on cell division and expansion, which are both regulated by complex gene networks. In several eudicot species belonging to the rosid clade, organ growth is controlled by a repressor complex consisting of PEAPOD (PPD) and KINASE-INDUCIBLE DOMAIN INTERACTING (KIX) proteins. The role of these proteins in asterids, which together with the rosids constitute most of the core eudicot species, is unknown. We used Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-associated protein 9 genome editing to target SlKIX8 and SlKIX9 in the asterid model species tomato (Solanum lycopersicum) and analyzed loss-of-function phenotypes. Loss-of-function of SlKIX8 and SlKIX9 led to the production of enlarged, dome-shaped leaves and these leaves exhibited increased expression of putative Solanum lycopersicum PPD (SlPPD target genes. Unexpectedly, kix8 kix9 mutants carried enlarged fruits with increased pericarp thickness due to cell expansion. At the molecular level, protein interaction assays indicated that SlKIX8 and SlKIX9 act as adaptors between the SlPPD and SlTOPLESS co-repressor proteins. Our results show that KIX8 and KIX9 are regulators of organ growth in asterids and can be used in strategies to improve important traits in produce such as thickness of the fruit flesh.

Caracterización clínica de pacientes con gangrena de Fournier del Hospital General Docente "Dr. Agostinho Neto", 2008-2018 / Clinical characterization of patients with Fournier's gangrene at the Hospital General Docente "Dr. Agostinho Neto", 2008-2018 / Caracterização clínica de pacientes com gangrena de Fournier no Hospital Geral de Ensino "Dr. Agostinho Neto", 2008-2018

RESUMEN Introducción: La gangrena de Fournier se define como una forma específica de fascitis necrotizante Tipo I, que constituye una emergencia urológica, poco frecuente y de elevada mortalidad. Objetivo: Caracterizar la gangrena de Fournier en los pacientes atendidos en el servicio de Urología del Hospital General Docente "Dr. Agostinho Neto" en el periodo enero 2008 - diciembre 2018. Método: Se realizó un estudio descriptivo de variables demográficas y clínicas (edad, sexo, mortalidad, comorbilidad, causas desencadenantes, sitio primario de la infección, sitio de extensión de la infección, estadía hospitalaria) en 20 pacientes. La historia clínica fue la fuente de información primaria. Los datos fueron procesados mediante el programa estadístico SPSS versión 20.0, y se utilizó la estadística descriptiva para determinar las frecuencias absolutas y relativas (porcentajes) y media. Resultados: El 100 % correspondió a varones con un promedio de edad de 64,0 años (27-92); la mortalidad fue del 40 %. La diabetes mellitus fue la comorbilidad más frecuente en 10 pacientes (50,0 %), 12 (60,0 %) tenían más de un proceso comórbido. Las lesiones cutáneas constituyeron la causa primaria en 11 (55,0 %), y los escrotos fueron el principal sitio de origen de la infección en el 55,0 %. El promedio de estadía hospitalaria fue de 37,7 días (7-75 días). Conclusiones: La correcta evaluación de las variables demográficas y clínicas es necesaria para establecer un correcto diagnóstico y plan de tratamiento.

ABSTRACT Introduction: Fournier's gangrene is defined as a specific form of Type I necrotizing fasciitis, which constitutes a rare urological emergency with high mortality. Objective: To characterize Fournier's gangrene in patients treated in the Urology service of the Hospital General Docente "Dr. Agostinho Neto" in the period from January 2008 to December 2018. Method: A descriptive study of demographic and clinical variables (age, gender, mortality, comorbidity, triggering causes, primary site of infection, site of extension of the infection, hospital stay) was carried out in 20 patients. The medical history was the primary source of information. The data were processed using the statistical program SPSS, version 20.0, and descriptive statistics were used to determine the absolute and relative frequencies (percentages) and mean. Results: 100% corresponded to men with an average age of 64.0 years (27-92); mortality made a 40%. Diabetes mellitus was the most frequent comorbidity, in 10 of the patients (50.0%); 12 patients (60.0%) had more than one comorbid process. Skin lesions were the primary cause in 11 (55.0%), and the scrotum was the main site of origin of infection in 55.0%. The mean hospital stay was 37.7 days (7-75 days). Conclusions: The correct evaluation of the demographic and clinical variables is necessary to establish a correct diagnosis and treatment plan.

RESUMO Introdução: A gangrena de Fournier é definida como uma forma específica de fasceíte necrosante tipo I, que se constitui em uma rara emergência urológica com alta mortalidade. Objetivo: Caracterizar a gangrena de Fournier em pacientes atendidos no serviço de Urologia do Hospital Geral Universitário "Dr. Agostinho Neto" no período de janeiro de 2008 a dezembro de 2018. Método: Estudo descritivo de variáveis demográficas e clínicas (idade, sexo, mortalidade, comorbidade, causas desencadeantes, sítio primário de infecção, extensão do sítio de infecção, internação) em 20 pacientes. O histórico médico foi a principal fonte de informação. Os dados foram processados no programa estatístico SPSS versão 20.0, e a estatística descritiva foi utilizada para determinar as frequências absolutas e relativas (percentuais) e a média. Resultados: 100% corresponderam a homens com idade média de 64,0 anos (27-92); a mortalidade foi de 40%. Diabetes mellitus foi a comorbidade mais frequente em 10 pacientes (50,0%), 12 (60,0%) apresentaram mais de um processo comórbido. Lesões cutâneas foram a causa primária em 11 (55,0%), e o escroto foi o principal sítio de origem da infecção em 55,0%. O tempo médio de internação foi de 37,7 dias (7-75 dias). Conclusões: A correta avaliação das variáveis demográficas e clínicas é necessária para estabelecer um correto diagnóstico e plano de tratamento.

Complex cellular and molecular events determining fruit size.

The understanding of plant organ-size determination represents an important challenge, especially because of the significant role of plants as food and renewable energy sources and the increasing need for plant-derived products. Most of the knowledge on the regulation of organ growth and the molecular network controlling cell division and cell expansion, the main drivers of growth, is derived from arabidopsis. The increasing use of crops such as tomato for research is now bringing essential information on the mechanisms underlying size control in agronomically important organs. This review describes our current knowledge, still very scarce, of the cellular and molecular mechanisms governing tomato fruit size and proposes future research to better understand the regulation of growth in this important crop.

In search of the still unknown function of FW2.2/CELL NUMBER REGULATOR, a major regulator of fruit size in tomato.

The FW2.2 gene is associated with the major quantitative trait locus (QTL) governing fruit size in tomato, and acts by negatively controlling cell division during fruit development. FW2.2 belongs to a multigene family named the CELL NUMBER REGULATOR (CNR) family. CNR proteins harbour the uncharacterized PLAC8 motif made of two conserved cysteine-rich domains separated by a variable region that are predicted to be transmembrane segments, and indeed FW2.2 localizes to the plasma membrane. Although FW2.2 was cloned more than two decades ago, the molecular mechanisms of action remain unknown. In particular, how FW2.2 functions to regulate cell cycle and fruit growth, and thus fruit size, is as yet not understood. Here we review current knowledge on PLAC8-containing CNR/FWL proteins in plants, which are described to participate in organogenesis and the regulation of organ size, especially in fruits, and in cadmium resistance, ion homeostasis, and/or Ca2+ signalling. Within the plasma membrane FW2.2 and some CNR/FWLs are localized in microdomains, which is supported by recent data from interactomics studies. Hence FW2.2 and CNR/FWL could be involved in a transport function of signalling molecules across membranes, influencing organ growth via a cell to cell trafficking mechanism.

The PEAPOD Pathway and Its Potential To Improve Crop Yield.

A key strategy to increase plant productivity is to improve intrinsic organ growth. Some of the regulatory networks underlying organ growth and development, as well as the interconnections between these networks, are highly conserved. An example of such a growth-regulatory module with a highly conserved role in final organ size and shape determination in eudicot species is the PEAPOD (PPD)/KINASE-INDUCIBLE DOMAIN INTERACTING (KIX)/STERILE APETALA (SAP) module. We review the proteins constituting the PPD pathway and their roles in different plant developmental processes, and explore options for future research. We also speculate on strategies to exploit knowledge about the PPD pathway for targeted yield improvement to engineer crop traits of agronomic interest, such as leaf, fruit, and seed size.

Emerging Connections between Small RNAs and Phytohormones.

Small RNAs (sRNAs), mainly including miRNAs and siRNAs, are ubiquitous in eukaryotes. sRNAs mostly negatively regulate gene expression via (post-)transcriptional gene silencing through DNA methylation, mRNA cleavage, or translation inhibition. The mechanisms of sRNA biogenesis and function in diverse biological processes, as well as the interactions between sRNAs and environmental factors, like (a)biotic stress, have been deeply explored. Phytohormones are central in the plant's response to stress, and multiple recent studies highlight an emerging role for sRNAs in the direct response to, or the regulation of, plant hormonal pathways. In this review, we discuss recent progress on the unraveling of crossregulation between sRNAs and nine plant hormones.

Comparative transcriptomics enables the identification of functional orthologous genes involved in early leaf growth.

Leaf growth is a complex trait for which many similarities exist in different plant species, suggesting functional conservation of the underlying pathways. However, a global view of orthologous genes involved in leaf growth showing conserved expression in dicots and monocots is currently missing. Here, we present a genome-wide comparative transcriptome analysis between Arabidopsis and maize, identifying conserved biological processes and gene functions active during leaf growth. Despite the orthology complexity between these distantly related plants, 926 orthologous gene groups including 2829 Arabidopsis and 2974 maize genes with similar expression during leaf growth were found, indicating conservation of the underlying molecular networks. We found 65% of these genes to be involved in one-to-one orthology, whereas only 28.7% of the groups with divergent expression had one-to-one orthology. Within the pool of genes with conserved expression, 19 transcription factor families were identified, demonstrating expression conservation of regulators active during leaf growth. Additionally, 25 Arabidopsis and 25 maize putative targets of the TCP transcription factors with conserved expression were determined based on the presence of enriched transcription factor binding sites. Based on large-scale phenotypic data, we observed that genes with conserved expression have a higher probability to be involved in leaf growth and that leaf-related phenotypes are more frequently present for genes having orthologues between dicots and monocots than clade-specific genes. This study shows the power of integrating transcriptomic with orthology data to identify or select candidates for functional studies during leaf development in flowering plants.

Molecular networks regulating cell division during Arabidopsis leaf growth.

Leaves are the primary organs for photosynthesis, and as such have a pivotal role for plant growth and development. Leaf development is a multifactorial and dynamic process involving many genes that regulate size, shape, and differentiation. The processes that mainly drive leaf development are cell proliferation and cell expansion, and numerous genes have been identified that, when ectopically expressed or down-regulated, increase cell number and/or cell size during leaf growth. Many of the genes regulating cell proliferation are functionally interconnected and can be grouped into regulatory modules. Here, we review our current understanding of six important gene regulatory modules affecting cell proliferation during Arabidopsis leaf growth: ubiquitin receptor DA1-ENHANCER OF DA1 (EOD1), GROWTH REGULATING FACTOR (GRF)-GRF-INTERACTING FACTOR (GIF), SWITCH/SUCROSE NON-FERMENTING (SWI/SNF), gibberellin (GA)-DELLA, KLU, and PEAPOD (PPD). Furthermore, we discuss how post-mitotic cell expansion and these six modules regulating cell proliferation make up the final leaf size.

cis-Cinnamic acid is a natural plant growth-promoting compound.

Agrochemicals provide vast potential to improve plant productivity, because they are easy to implement at low cost while not being restricted by species barriers as compared with breeding strategies. Despite the general interest, only a few compounds with growth-promoting activity have been described so far. Here, we add cis-cinnamic acid (c-CA) to the small portfolio of existing plant growth stimulators. When applied at low micromolar concentrations to Arabidopsis roots, c-CA stimulates both cell division and cell expansion in leaves. Our data support a model explaining the increase in shoot biomass as the consequence of a larger root system, which allows the plant to explore larger areas for resources. The requirement of the cis-configuration for the growth-promoting activity of CA was validated by implementing stable structural analogs of both cis- and trans-CA in this study. In a complementary approach, we used specific light conditions to prevent cis/trans-isomerization of CA during the experiment. In both cases, the cis-form stimulated plant growth, whereas the trans-form was inactive. Based on these data, we conclude that c-CA is an appealing lead compound representing a novel class of growth-promoting agrochemicals. Unraveling the underlying molecular mechanism could lead to the development of innovative strategies for boosting plant biomass.

A genetics screen highlights emerging roles for CPL3, RST1 and URT1 in RNA metabolism and silencing.

Post-transcriptional gene silencing (PTGS) is a major mechanism regulating gene expression in higher eukaryotes. To identify novel players in PTGS, a forward genetics screen was performed on an Arabidopsis thaliana line overexpressing a strong growth-repressive gene, ETHYLENE RESPONSE FACTOR6 (ERF6). We identified six independent ethyl-methanesulfonate mutants rescuing the dwarfism of ERF6-overexpressing plants as a result of transgene silencing. Among the causative genes, ETHYLENE-INSENSITIVE5, SUPERKILLER2 and HASTY1 have previously been reported to inhibit PTGS. Notably, the three other causative genes have not, to date, been related to PTGS: UTP:RNA-URIDYLYLTRANSFERASE1 (URT1), C-TERMINAL DOMAIN PHOSPHATASE-LIKE3 (CPL3) and RESURRECTION1 (RST1). We show that these genes may participate in protecting the 3' end of transgene transcripts. We present a model in which URT1, CPL3 and RST1 are classified as PTGS suppressors, as compromisation of these genes provokes the accumulation of aberrant transcripts which, in turn, trigger the production of small interfering RNAs, initiating RNA silencing.