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The cerato-mandibular ligament: a key functional trait for grazing in damselfishes (Pomacentridae)

Damien Olivier Bruno Frederich MILTON ALEJANDRO SPANOPOULOS ZARCO Eduardo Francisco Balart Páez Eric Parmentier (2014, [Artículo])

"The success of a taxonomic group can be promoted by a key character that allows the group to interact with its environment in a different way and to potentially occupy new niches. The Pomacentridae possess a synapomorphic trait, the cerato-mandibular (c-md) ligament, which joins the hyoid bar to the inner part of the lower jaw. It has previously been shown that this ligament is a key trait in communication in damselfishes because it enables them to slam the oral jaws shut causing teeth collision and sound production. This specific behavior of mouth closing could, however, also be used for other tasks, such as feeding. Many territorial damselfishes are referred to as farmers, due to their ability to manage algal crops on which they feed. This study hypothesizes that the c-md ligament provides an advantage for grazing filamentous algae, and should thus be considered a key trait for farming behavior."

Biomechanics, Evolution, Farming, Functional morphology BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) ZOOLOGÍA MARINA ZOOLOGÍA MARINA

De Novo assembly and annotation of the Pacific calico scallop (Argopecten ventricosus) transcriptome for immune-related gene discovery

RUTH ESCAMILLA MONTES GENARO DIARTE PLATA GABRIELA BERENICE MENDOZA MALDONADO Aarón Barraza Celis Carlos Eliud Angulo Valadez Seyed Hossein Hoseinifar Jesús Arturo Fierro Coronado ANTONIO LUNA GONZALEZ (2022, [Artículo])

"Invertebrates' immune defense mechanisms play a critical role in pathogen recognition and elimination. De novo assembly and annotation of the Argopecten ventricosus transcriptome were performed for the immune-related gene identification. Scallops (height: 4.4 cm) were challenged with inactivated Vibrio parahaemolyticus IPNGS16. The RNA from different tissues was pooled for a single cDNA library construction sequenced by NextSeq 500 platform 2×75 paired‐end chemistry. Before de novo assembling with Trinity, reads were analyzed with FastQC, Trimmomatic, and Prinseq. Assembled sequences were analyzed by CD-HIT-EST and TransDecoder. The corresponding annotation was performed against NCBI-nr, RefSeq protein, and KAAS (KEGG) databases. The Trinity assembly yielded 107,516 contigs. TransDecoder yielded 25,285 sequences as CDSs of which, 16,123 were annotated against the NCBI-nr protein, most of them scored with Crassostrea gigas data. Gene ontology mapped sequences (15,262) were classified in molecular functions (~13,000), cellular components (~11,000), and biological processes (~13,000). The KAAS analysis showed biological categories for metabolism (13%), cellular processes (12%), genetic information processing (10%), organismal systems (19%), environmental information (13%), and human diseases (33 %). Within the organismal systems, 467 immune-related genes (KO) were identified. Sixty-four immune-related genes were annotated/blasted against the NCBI-nr and RefSeq protein databases. An RT-qPCR was performed to analyze the expression level of immune-related genes obtained in the transcriptome analysis in scallops (height 4.5 cm) treated with probiotic bacilli added to culture water. Bacilli significantly increased the expression of the HSP70 and PGRP genes. The gene transcripts analysis of A. ventricosus will better understand its immune response against pathogens in culture systems."

Argopecten ventricosus, calico scallop, transcriptome, bivalve, immune genes BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) INMUNOLOGÍA INMUNOLOGÍA

Gene expression in primary hemocyte culture of the Pacific white shrimp Penaeus vannamei infected with different white spot syndrome virus (WSSV) strains

Delia Patricia Parrilla Taylor REGINA ELIZONDO GONZALEZ Jesús Neftalí Gutiérrez Rivera SILVIA ALEJANDRA GARCIA GASCA NORBERTO VIBANCO PEREZ MA. DE JESUS DURAN AVELAR RICARDO VAZQUEZ JUAREZ (2022, [Artículo])

"Five previously analyzed white spot syndrome virus (WSSV) strains from northwest Mexico,differing in their genome architecture as well as in virulence, were selected (high virulence JP and LG strains;moderate virulence GVE and DIV strains; and low virulence LC10 strain) to evaluate pathogenesis response in vitro. Expression of phagocytosis-activating protein PAP, manganese superoxide dismutase MnSOD and peroxiredoxin PRX, and two genes of immediate-early expression (IE1 and WSSV304) were measured by qPCR in a primary hemocyte cell culture from Penaeus vannamei at 1, 3, 6, 12, and 24 h post-infection (hpi). PAP expression was significantly higher at 1 and 3 hpi, and JP and LC10 strains induced the highest expression. The response of MnSOD was high at 1 hpi, and a significant increase in PRX expression was detected at 3 hpi, probably due to the occurrence of an oxidative burst; expression levels of MnSOD and PRX were significantly higher at 1 and 3 hpi, respectively, induced by the LG strain (high virulence), suggesting an acute response. In general, expression of most immune-related - genes decreased after the initial hours of infection. Expression levels of IE1 and WSSV304 were exceptionally high at 1 hpi in almost all five WSSV analyzed strains,confirming their efficient mechanism for replication and viral fitness. The results of this study do not show an accurate link between the genome size and WSSV virulence of the strains, albeit the strain with the smallest genome showed the highest virulence. All strains induced an early immune response in heterogeneous ways."

Penaeus vannamei, virulence, gene expression, viral fitness, viral pathogenesis, immune response BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) PATOLOGÍA ANIMAL PATOLOGÍA ANIMAL

Screening of xylose utilizing and high lipid producing yeast strains as a potential candidate for industrial application

Linnea Qvirist RICARDO VAZQUEZ JUAREZ Thomas Andlid (2022, [Artículo])

"Background: Sustainable production of oil for food, feed, fuels and other lipid-based chemicals is essential to meet the demand of the increasing human population. Consequently, novel and sustainable resources such as lignocel- lulosic hydrolysates and processes involving these must be explored. In this paper we screened for naturally-occurring xylose utilizing oleaginous yeasts as cell factories for lipid production, since pentose sugar catabolism plays a major role in efcient utilization of lignocellulosic feedstocks. Glycerol utilization, which is also benefcial in yeast-based oil production as glycerol is a common by-product of biodiesel production, was investigated as well. Natural yeast isolates were studied for lipid accumulation on a variety of substrates, and the highest lipid accumulating strains were further investigated in shake fask cultivations and fermenter studies on xylose and hydrolysate. Results: By collecting leaves from exotic plants in greenhouses and selective cultivation on xylose, a high frequency of oleaginous yeasts was obtained (>40%). Diferent cultivation conditions lead to diferences in fatty acid contents and compositions, resulting in a set of strains that can be used to select candidate production strains for diferent purposes. In this study, the most prominent strains were identifed as Pseudozyma hubeiensis BOT-O and Rhodosporidium toruloides BOT-A2. The fatty acid levels per cell dry weight after cultivation in a nitrogen limited medium with either glucose, xylose or glycerol as carbon source, respectively, were 46.8, 43.2 and 38.9% for P. hubeiensis BOT-O, and 40.4, 27.3 and 42.1% for BOT-A2. Furthermore, BOT-A2 accumulated 45.1% fatty acids per cell dry weight in a natural plant hydrolysate, and P. hubeiensis BOT-O showed simultaneous glucose and xylose consumption with similar growth rates on both carbon sources. The fatty acid analysis demonstrated both long chain and poly-unsaturated fatty acids, depending on strain and medium. Conclusions: We found various natural yeast isolates with high lipid production capabilities and the ability to grow not only on glucose, but also xylose, glycerol and natural plant hydrolysate. R. toruloides BOT-A2 and P. hubeiensis BOT-O specifcally showed great potential as production strains with high levels of storage lipids and comparable growth to that on glucose on various other substrates, especially compared to currently used lipid production strains..."

Microbial lipids, Oleaginous yeast, Lignocellulose, Pseudozyma hubeiensis, Rhodosporidium toruloides BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA MICROBIOLOGÍA

Evaluación de las propiedades del mantillo en plantaciones de restauración ecológica en la selva estacional

GERARDO ANTONIO ROJAS ROBLES (2023, [Tesis de maestría])

En México, la selva estacionalmente seca también llamada selva baja caducifolia o

bosque tropical caducifolio presenta altas tasas de deforestación y degradación

debido a las actividades antrópicas. La intervención de restauración puede revertir

la pérdida de la diversidad biológica, así como promover la recuperación de los

beneficios de la naturaleza para las personas. Las plantaciones de restauración se

pueden establecer con especies de diferente estado sucesional o grupo funcional.

El aumento de la riqueza de leñosas debido a las plantaciones establecidas y al

proceso de sucesión natural pueden favorecer la acumulación de mantillo. Este

trabajo evaluó la acumulación de mantillo debido al proceso de sucesión natural y

al efecto de siete combinaciones de plantación incluyendo seis especies

leguminosas y seis no leguminosas en la temporada de lluvias (julio y septiembre

2021) y de secas (diciembre 2021 y marzo 2022). Después de cuatro años del

establecimiento del experimento, la masa de mantillo fue más alta en las

plantaciones que en la sucesión natural pero no difirió entre estaciones,

probablemente debido a la baja cantidad de lluvia que disminuyó el crecimiento de

los árboles, la caída de hojarasca y la tasa de descomposición de esta. El

crecimiento y la riqueza de las leñosas en las plantaciones y de las especies

reclutadas naturalmente en todos los tratamientos explicaron la masa de mantillo.

In Mexico, the tropical dry forest also called lowland deciduous forest or tropical

deciduous forest shows high rates of deforestation and degradation due to

anthropogenic activities. Restoration intervention can reverse the loss of

biodiversity, as well as promote the recovery of the nature's benefits to people.

Restoration plantings can be established with species of different successional

status or functional group. Increased woody richness due to plantings and natural

succession can lead to the accumulation of mulch mass. This work evaluated the

change in litter mass due to the natural succession process and the early effect of

seven combinations of restoration plantings of six legumes and six non-legume

species during the rainy (July and September 2021) and the dry season (December

2021 and March 2022). After four years of the establishment of experiment, the

mulch mass was higher in the plantings than under natural succession, but it did not

differ between seasons probably because the low amount of rain affected the growth

rates of plants, the amount of litter and the rate of litter decomposition. Tree growth

and richness of plantings or and of those from natural recruitment at all treatments

explained mulch mass.

BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA

Compuestos bioactivos presentes en geopropóleos de Melipona beecheii y su potencial uso en la medicina tradicional

ANGEL DANIEL HERRERA ESPAÑA OMAR ARISTEO PEÑA MORAN ROGER GASPAR CAUICH KUMUL (2023, [Artículo])

El interés actual por estudios con productos naturales, ha llevado a realizar investigaciones con geopropóleos. Este producto natural producido por especies de abejas sin aguijón (meliponinos), resulta de una mezcla de material resinoso vegetal, arcilla y secreciones salivales. Estudios farmacológicos realizados con extractos de geopropóleos de Melipona beecheii, han demostrado sus propiedades anticancerígenas, antimicrobianas y antioxidantes, las cuales se relacionan con la presencia de diversos compuestos bioactivos. Debido a sus propiedades terapéuticas, este producto natural puede ser considerado como una potencial alternativa dentro de la medicina tradicional maya.

ABEJA SIN AGUIJON ACTIVIDAD ANTIMICROBIANA FENOLES FLAVONOIDES PROPIEDADES TERAPEUTICAS BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) INVERTEBRADOS INVERTEBRADOS

Do marine reserves increase prey for California sea lions and Pacific harbor seals?

ALEJANDRO ARIAS DEL RAZO (2019, [Artículo])

Community marine reserves are geographical areas closed to fishing activities, implemented and enforced by the same fishermen that fish around them. Their main objective is to recover commercial stocks of fish and invertebrates. While marine reserves have proven successful in many parts of the world, their success near important marine predator colonies, such as the California sea lion (Zalophus californianus) and the Pacific harbor seal (Phoca vitulina richardii), is yet to be analyzed. In response to the concerns expressed by local fishermen about the impact of the presence of pinnipeds on their communities’ marine reserves, we conducted underwater surveys around four islands in the Pacific west of the Baja California Peninsula: two without reserves (Todos Santos and San Roque); one with a recently established reserve (San Jeronimo); and, a fourth with reserves established eight years ago (Natividad). All these islands are subject to similar rates of exploitation by fishing cooperatives with exclusive rights. We estimated fish biomass and biodiversity in the seas around the islands, applying filters for potential California sea lion and harbor seal prey using known species from the literature. Generalized linear mixed models revealed that the age of the reserve has a significant positive effect on fish biomass, while the site (inside or outside of the reserve) did not, with a similar result found for the biomass of the prey of the California sea lion. Fish biodiversity was also higher around Natividad Island, while invertebrate biodiversity was higher around San Roque. These findings indicate that marine reserves increase overall fish diversity and biomass, despite the presence of top predators, even increasing the numbers of their potential prey. Community marine reserves may help to improve the resilience of marine mammals to climate-driven phenomena and maintain a healthy marine ecosystem for the benefit of both pinnipeds and fishermen. © 2019 Arias-Del-Razo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, biodiversity, biomass, climate change, ecosystem resilience, environmental exploitation, fish stock, fishing, marine environment, marine invertebrate, nonhuman, Phoca vitulina, Pinnipedia, prey searching, Zalophus californianus, animal, biom BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) BIOLOGÍA ANIMAL (ZOOLOGÍA)

Interaction between plants growing together from germination to 2 years: A test of competition and phylogenetic closeness for Northeastern Mexico

Interacción entre plantas coexistiendo desde la germinación hasta los 2 años: un experimento de competencia y cercanía filogenética en el noreste de México

ENRIQUE JURADO YBARRA Joel David Flores Rivas Jonathan Marroquín MARISELA PANDO MORENO DAVID ALBERTO RODRIGUEZ TRAPERO Humberto González Rodríguez José Alejandro Selvera Mancha Juan Ángel López Carmona (2022, [Artículo])

"Competition and facilitation are important factors affecting seedling survival. These factors probably affect plant distribution and abundance. Interactions between species relate to phylogeny, in that closely related species are likely to compete more for resources and facilitation is expected between more distantly related species. We tested for Tamaulipan thornscrub plants, grown with close and distant relatives if they differed in survival, length and weight of shoots and roots, assuming that closely related species would compete more than distant ones. We also explored whether seed mass was associated with plant size from 1-24 months after germination. We grew plants from Tamaulipan thornscrub, with a sibling or with one individual from other species from 1-24 months. Seedling survival was similar for all species when their seedlings grew alone or under competition, at 1, 6 and 12 months. At 24 months seedling survival of Vachellia farnesiana was lower when grown with Havardia pallens. There was no evidence of stronger competition or facilitation for phylogenetically closer species. Seedling size correlated with seed mass one month after germination but not after 6 months. Maximum and mean adult plant height did not correlate with seed mass or with plant height in our trials. We found no evidence of phylogeny explaining nearest neighbors in competition during germination for Tamaulipan thornscrub."

"La competencia y la facilitación son factores importantes que afectan la supervivencia de las plántulas y probablemente afectan la distribución y abundancia de las plantas. Las interacciones entre especies se relacionan con la filogenia, es probable que las especies estrechamente relacionadas compitan más por recursos y que en las menos emparentadas ocurra facilitación. Se investigó si plantas de matorral tamaulipeco creciendo junto a parientes cercanos y lejanos diferían en supervivencia, longitud y peso de tallos y raíces, asumiendo que las especies estrechamente relacionadas competirían más que las lejanas. También se exploró si el peso de semillas se asoció con el tamaño de la planta entre 1 y 24 meses de edad. Se pusieron a crecer plantas de matorral tamaulipeco, con un hermano o con un individuo de otras especies, de 1-24 meses. La supervivencia de plántulas fue similar para todas las especies cuando éstas crecieron solas o en competencia, a los 1, 6 y 12 meses. A los 24 meses, la supervivencia de plántulas de Vachellia farnesiana fue menor cuando creció con Havardia pallens. No hubo evidencia de una competencia o facilitación fuerte para especies filogenéticamente más cercanas. El tamaño de la plántula se correlacionó con el peso de la semilla únicamente al mes de germinadas. La altura máxima y promedio de la planta adulta no se correlacionó con el peso de semillas o con la altura de la planta. La filogenia no explicó la competencia con los vecinos más cercanos durante la germinación de especies del matorral tamaulipeco."

Phylogeny Seed mass Seedling Shoot/root ratio Tamaulipan thornscrub BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) BIOLOGÍA VEGETAL (BOTÁNICA)

Influencia de la exposición a metales pesados sobre Sphenarium purpurascens (Orthoptera:Pygomorphidae): Un estudio multibiomarcador

JANETH ESTEVES AGUILAR (2024, [Tesis de doctorado])

México es conocido como uno de los sectores minero-metalúrgico más importantes en el mundo debido a la diversidad de tipologías de depósitos minerales que contiene (Servicio Geológico Mexicano, 2017) repartidos en 26 estados (Secretaría de Economía, 2023). A nivel mundial, México se posicionó en el 2022 como el primer productor de plata (Ag) (Secretaría de Economía, 2022), y ocupa el cuarto lugar en la producción de plomo (Pb), quinto en molibdeno (Mo), sexto en cadmio (Cd), séptimo en zinc (Zn) y noveno en oro (Au) (CAMIMEX, 2023).

BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA

COLECTORES DE ALGAS DE MÉXICO (1787-1954)

JOSE LUIS GODINEZ ORTEGA (2008, [Artículo])

Se presenta información biográfica y bibliográfica de los colectores de algas de México durante el período de 1787-1954. Los datos fueron obtenidos mediante la consulta de herbarios nacionales y extranjeros, la comunicación directa con los curadores de los mismos y la revisión de la bibliografía pertinente. Se encontraron 51 datos correspondientes a colectores, principalmente de origen norteamericano y europeo; el material colectado por los mismos fue depositado en 16 herbarios: ocho europeos, siete americanos y uno australiano. El trabajo de los colectores reúne información ficoflorística general de los phyla: Cyanobacteria, Rhodophyta, Ochrophyta (incluye Phaeophyceae y Xanthophyceae), Bacillariophyta, Chlorophyta y Charophyta; siendo los mejor representados Bacillariophyta y Rhodophyta. Se incluyen las fechas y localidades de las regiones estudiadas en 26 estados del país. En el periodo que abarca el estudio se descubrieron aproximadamente 477 nuevas especies.

BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) BOTÁNICA GENERAL BOTÁNICA GENERAL