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Acorn size and tolerance to seed predators:the multiple roles of acorns as food for seed predators,fruit for dispersal and fuel for growth

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integrative Zoology 2018年第3期13卷 251-266页

作者： Andrew W.BARTLOW Salvatore JAGOSTA Rachel CURTIS Xianfeng YI Michael ASTEELE department of Biology and The WIESS Institute for Environmental Science and Sustainability Wilkes UniversityWilkes BarrePennsylvaniaUSA present address:department of Biology University of UtahSalt Lake CityUtahUSA Center for Environmental Studies and department of Biology Virginia Commonwealth UniversityRichmondVirginiaUSA Present address:Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege StationTexasUSA College of Life Sciences Jiangxi Normal UniversityNanchangJiangxiChina.

Fitness of parents and offspring is affected by offspring size.In oaks(Quercus spp.),acorns vary considerably in size across,and within,species.Seed size influences dispersal and establishment of oaks,but it is not known whether size imparts tolerance to seed predators.Here,we examine the relative extent to which cotyledon size serves as both a means for sustaining partial consumption and energy reserves for developing seedlings during early stages of establishment.Acorns of 6 oak species were damaged to simulate acorn predation by vertebrate and invertebrate seed predators.Seedling germination/emergence and growth rates were used to assess seedling performance.We predicted that if cotyledons are important for dispersal,acorns should show tolerance to partial seed consumption.Alternatively,if the cotyledon functions primarily as an energy reserve,damage should significantly influence seedling performance.Acorns of each species germinated and produced seedlings even after removing>50%of the cotyledon.Seed mass explained only some of the variation in performance.Within species,larger acorns performed better than smaller acorns when damaged.Undamaged acorns performed as well or better than damaged acorns.There was no pattern among individual species with increasing amounts of damage.In some species,simulated invertebrate damage resulted in the poorest performance,suggesting alternative strategies of oaks to sustain damage.Large cotyledons in acorns may be important for attracting seed dispersers and sustaining partial damage,while also providing energy to young seedlings.Success of oak establishment may follow from the resilience of acorns to sustain damage at an early stage.

关键词： acorns damage tolerance dispersal Quercus seed size

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Integrins and their potential roles in mammalian pregnancy

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Journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： Gregory A.Johnson Robert C.Burghardt Fuller W.Bazer Heewon Seo Joe W.Cain department of veterinary integrative biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the scientific literature, the illustrations in this m

关键词： Humans Implantation Integrins Pigs Pregnancy Rodents Sheep

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RIP1 （ROP Interactive Partner 1）/ICR1 Marks Pollen Germination Sites and May Act in the ROP1 Pathway in the Control of Polarized Pollen Growth

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Molecular Plant 2008年第6期1卷 1021-1035页

作者： Shundai Li Ying Gu An Yan Elizabeth Lord Zhen-Biao Yang Center for Plant Cell Biology Institute of Integrative Genome Biology and Department of Botany and Plant Sciences University of California Riverside CA92521 USA present address: Energy biosciences Institute University of California Berkeley Berkeley CA 94720 USA

Rho family small GTPases are universal signaling switches in the control of cell polarity in eukaryotic cells. Their polar distribution to the cell cortex is critical for the execution of their functions, yet the mechanism for this distribution is poorly understood. Using a yeast two-hybrid method, we identified RIP1 （ROP interactive partner 1）, which belongs to a family of five members of novel proteins that share a C-terminal region that interacts with ROP. When expressed in Arabidopsis pollen, green fluorescence protein GFP-tagged RIP1 was localized to the nucleus of mature pollen. When pollen grains were hydrated in germination medium, GFP-RIP1 switched from the nucleus to the cell cortex at the future pollen germination site and was maintained in the apical cortex of germinating pollen and growing pollen tubes. RIP1 was found to interact with ROP1 in pollen tubes, and the cortical RIP1 localization was influenced by the activity of ROP1. Overexpression of RIP1 induced growth depolarization in pollen tubes, a phenotype similar to that induced by ROP1 overexpression. Interestingly, RIP1 overexpression enhanced GFP-ROP1 recruitment to the plasma membrane （PM） of pollen tubes. Based on these observations, we hypothesize that RIP1 is involved in the positive feedback regulation of ROP1 localization to the PM, leading to the establishment of a polar site for pollen germination and pollen tube growth.

关键词： Pollen Tube Retinopathy of Prematurity RIPK1 gene FEEDBACK REGULATION Nucleus Pollen pollen germination Two-Hybrid System Techniques Cell Polarity

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Analysis of per-and polyfluoroalkyl substances in Houston Ship Channel and Galveston Bay following a large-scale industrial fire using ion-mobility-spectrometry-mass spectrometry

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Journal of Environmental Sciences 2022年第5期34卷 350-362页

作者： Alan Valdiviezo Noor AAly Yu-Syuan Luo Alexandra Cordova Gaston Casillas MaKayla Foster Erin SBaker Ivan Rusyn Interdisciplinary Faculty of Toxicology Texas A&M UniversityCollege StationTX 77843USA department of veterinary integrative biosciences Texas A&M UniversityCollege StationTX 77843USA department of Environmental and Occupational Health Texas A&M UniversityCollege StationTX 77843USA department of Chemistry North Carolina State UniversityRaleighNC 27695USA

Per-and polyfluoroalkyl substances(PFAS)are persistent organic pollutants of concern be-cause of their ubiquitous presence in surface and ground water;analytical methods that can be used for rapid comprehensive exposure assessment and fingerprinting of PFAS are needed.Following the fires at the Intercontinental Terminals Company(ITC)in Deer Park,TX in 2019,large quantities of PFAS-containing firefighting foams were deployed.The release of these substances into the Houston Ship Channel/Galveston Bay(HSC/GB)prompted con-cerns over the extent and level of PFAS contamination.A targeted liquid chromatography-tandem mass spectrometry(LC-MS/MS)-based study of temporal and spatial patterns of PFAS associated with this incident revealed presence of 7 species;their levels gradually de-creased over a 6-month period.Because the targeted LC-MS/MS analysis was focused on about 30 PFAS molecules,it may have missed other PFAS compounds present in firefighting foams.Therefore,we utilized untargeted LC-ion mobility spectrometry-mass spectrome-try(LC-IMS-MS)-based analytical approach for a more comprehensive characterization of PFAS in these water samples.We analyzed 31 samples from 9 sites in the HSC/GB that were collected over 5 months after the incident.Our data showed that additional 19 PFAS were detected in surface water of HSC/GB,most of them decreased gradually after the incident.PFAS features detected by LC-MS/MS correlated well in abundance with LC-IMS-MS data;however,LC-IMS-MS identified a number of additional PFAS,many known to be compo-nents of firefighting foams.These findings therefore illustrate that untargeted LC-IMS-MS improved our understanding of PFAS presence in complex environmental samples.

关键词： Emergency Environmental disaster PFAS

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Mitotic Spindle Organization by the Preprophase Band

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Molecular Plant 2008年第6期1卷 950-960页

作者： J. Christian Ambrose Richard Cyr The Pennsylvania State University Department of Biology The Huck Institutes of the Life Sciences Integrative Biosciences Graduate Degree Program PlantPhysiology Program University Park PA 16802 USA present address: department of Botany University of British Columbia Vancouver British Columbia V6T 1Z4 Canada

In higher plants, the preprophase band （PPB） of microtubules （MTs） forecasts the cell division site prior to mitosis and specifies the organization of MTs into a bipolar prophase spindle surrounding the nucleus. However, the mechanisms governing this PPB-dependent establishment of bipolarity are unclear. Here, we present evidence from live cell imaging studies that suggest a role for the MTs bridging the PPB and the prophase nucleus in mediating this function. Results from drug treatments, along with genetic evidence from null kinesin plants, suggest that these MTs contribute to the bipolarity, orientation, and position of the prophase spindle. Specifically, the absence of these bridge MTs is associated with lack of bipolarity, while non-uniform distributions of bridge MTs correlate with prophase spindle migration, deformation, and enhanced bipolarity toward the region of highest bridge MT density. This behavior does not require actomyosin-based forces, and is enhanced by suppressing MT dynamics with taxol. These observations occur during late prophase, and are coincident with the gradual closing of annular spindle poles. Based on these data, we describe a hypothetical mechanism for bridge MT-dependent organization of prophase spindles.

关键词： preprophase band mitosis acentrosomal spindle microtubule kinesin ATK5 cytokinesis.

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Ovarian autoimmune disease： clinical concepts and anima models

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Cellular & Molecular Immunology 2014年第6期11卷 510-521页

作者： Bryce D Warren William K Kinsey Lynda K McGinnis Lane K Christenson Susmita Jasti Anne M Stevens Brian K Petroff Margaret G Petroff department of Anatomy and Cell Biology University of Kansas Medical Center Kansas City KS USA department of Molecular and integrative Physiology University of Kansas Medical Center Kansas City KS USA Research Center for Immunity and I mmunotherapies Children's Hospital and Regional Medical Center and Division of Rheumatology Department of Pediatrics University of Washington Seattle WA USA department of Internal Medicine University of Kansas Medical Center Kansas City KS USA present address: department of Pathobiology and Diagnostic Investigation Michigan State University College of Veterinary Medicine East Lansing MI USA

The ovary is not an immunologically privileged organ, but a breakdown in tolerogenic mechanisms for ovary-specific antigens has disastrous consequences on fertility in women, and this is replicated in murine models of autoimmune disease. Isolated ovarian autoimmune disease is rare in women, likely due to the severity of the disease and the inability to transmit genetic information conferring the ovarian disease across generations. Nonetheless, autoimmune oophoritis is often observed in association with other autoimmune diseases, particularly autoimmune adrenal disease, and takes a toll on both society and individual health. Studies in mice have revealed at least two mechanisms that protect the ovary from autoimmune attack. These mechanisms include control of autoreactive T cells by thymus-derived regulatory T cells, as well as a role for the autoimmune regulator （AIRE）, a transcriptional regulator that induces expression of tissue-restricted antigens in medullary thymic epithelial cells during development of T cells. Although the latter mechanism is incompletely defined, it is well established that failure of either results in autoimmune-mediated targeting and depletion of ovarian follicles. In this review, we will address the clinical features and consequences of autoimmune-mediated ovarian infertility in women, as well as the possible mechanisms of disease as revealed by animal models.

关键词：不育家庭特征卵巢卵巢炎模型动物生育力胸腺胰岛素小鼠

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FTY720,a sphingosine analog,altered placentome histoarchitecture in ewes

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Journal of Animal Science and Biotechnology 2020年第2期11卷 380-392页

作者： Kathrin A.Dunlap Bryan G.White David W.Erikson M.Carey Satterfield Christiane Pfarrer Guoyao Wu Fuller W.Bazer Robert C.Burghardt Kayla J.Bayless Greg A.Johnson department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Okanagan College Salmon Arm Campus Salmon ArmBritish ColumbiaCanada Endocrine Technologies Core Oregon National Primate Research CenterOregon Health&Science UniversityBeavertonORUSA department of Anatomy University of Veterinary Medicine HannoverBischofsholer Damm 1530173 HannoverGermany department of veterinary integrative biosciences College of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843USA department of Molecular and Cellular Medicine Texas A&M Health Science CenterCollege StationTX 77843USA

Background:The lysosphingolipid,sphingosine-1-phosphate,is a well-described and potent pro-angiogenic factor.Receptors,as well as the sphingosine phosphorylating enzyme sphingosine kinase 1,are expressed in the placentomes of sheep and the decidua of rodents;however,a function for this signaling pathway during pregnancy has not been established.The objective of this study was to investigate whether sphingosine-1-phosphate promoted angiogenesis within the placentomes of pregnant ewes.Ewes were given daily jugular injections of FTY720(2-amino-2[2-(−4-octylphenyl)ethyl]propate-1,3-diol hydrochloride),an S1P analog.Results:FTY720 infusion from days 30 to 60 of pregnancy did not alter maternal organ weights nor total number or mass of placentomes,but did alter placentome histoarchitecture.Interdigitation of caruncular crypts and cotyledonary villi was decreased,as was the relative area of cotyledonary tissue within placentomes.Also,the percentage of area occupied by cotyledonary villi per unit of placentome was increased,while the thickness of the caruncular capsule was decreased in ewes treated with FTY720.Further,FTY720 infusion decreased the number and density of blood vessels within caruncular tissue near the placentome capsule where the crypts emerge from the capsule.Finally,FTY720 infusion decreased asparagine and glutamine in amniotic fluid and methionine in allantoic fluid,and decreased the crown rump length of day 60 fetuses.Conclusions:While members of the sphingosine-1-phosphate signaling pathway have been characterized within the uteri and placentae of sheep and mice,the present study uses FTY720 to address the influence of S1P signaling on placental development.We present evidence that modulation of the S1P signaling pathway results in the alteration of caruncular vasculature,placentome architecture,abundance of amino acids in allantoic and amniotic fluids,and fetal growth during pregnancy in sheep.The marked morphological changes in placentome histoarchitecture,including alteration in the vasculature,may

关键词： Placentome Pregnancy Sheep Sphingosine1 phosphate(S1P)

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The community structure and microbial linkage of rumen protozoa and methanogens in response to the addition of tea seed saponins in the diet of beef cattle

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Journal of Animal Science and Biotechnology 2021年第1期12卷 272-281页

作者： Cui Tan Carlos A.Ramírez-Restrepo Ali Mujtaba Shah Rui Hu Matt Bell Zhisheng Wang Chris McSweeney Institute of Animal Nutrition Sichuan Agricultural UniversityChengdu 611130SichuanChina Commonwealth Scientific and Industrial Research Organisation CSIRO Agriculture and FoodAustralian Tropical Sciences and Innovation PrecinctJames Cook UniversityTownsville QLD 4811Australia present address:CR Eco-efficient Agriculture Consultancy(CREAC) 46 Bilbao PlaceBushland Beach QLD 4818Australia department of Livestock Production Shaheed Benazir Bhutto University of Veterinary and Animal SciencesSakrandSindh 67210Pakistan “Low Carbon Breeding Cattle and Safety Production” University Key Laboratory of Sichuan ProvinceYa’an 625014SichuanChina School of biosciences University of NottinghamSutton BoningtonLoughborough LE125RDUK CSIRO Agriculture Queensland BioScience PrecinctSt LuciaBrisbane QLD 4067Australia.

Background: This study investigated changes in rumen protozoal and methanogenic communities, along with the correlations among microbial taxa and methane(CH_4) production of six Belmont Red Composite beef steers fed tea seed saponins(TSS). Animals were fed in three consecutive feeding periods, a high-grain basal diet for 14 d(BD period) then a period of progressive addition of TSS to the basal diet up to 30 g/d for 20 d(TSS period), followed by the basal diet for 13 d without TSS(BDP post-control period).Results: The study found that TSS supplementation decreased the amount of the protozoal genus Entodinium and increased Polyplastron and Eudiplodinium genera. During BDP period, the protozoa community of steers did not return to the protozoal profiles observed in BD period, with higher proportions of Metadinium and Eudiplodinium and lower Isotricha. The addition of TSS was found to change the structure of methanogen community at the subgenus level by decreasing the abundance of methanogens in the SGMT clade and increasing the abundance of methanogens in the RO clade. The correlation analysis indicated that the abundance of SGMT clade methanogens were positively correlated with Isotricha, and Isotricha genus and SGMT clade methanogens were positively correlated with CH_4 production. While RO clade were positively correlated with the proportion of Metadinium genus, which was negatively correlated with CH_4 emission.Conclusions: These results suggest that different genera of rumen protozoa ciliates appear to be selectively inhibited by TSS, and the change in methanogen community at the subgenus level may be due to the mutualistic relationships between methanogens and rumen ciliates.

关键词： Beef steers Methane Methanogen Protozoa Tea seed saponin

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