AtGRP3 is implicated in root size and aluminum response pathways in Arabidopsis

AtGRP3 is a glycine-rich protein (GRP) from Arabidopsis thaliana shown to interact with the receptor-like kinase AtWAK1 in yeast, in vitro and in planta. In this work, phenotypic analyses using transgenic plants were performed in order to better characterize this GRP. Plants of two independent knockout alleles of AtGRP3 develop longer roots suggesting its involvement in root size determination. Confocal microscopy analysis showed an abnormal cell division and elongation in grp3-1 knockout mutants. Moreover, we also show that grp3-1 exhibits an enhanced Aluminum (Al) tolerance, a feature also described in AtWAK1 overexpressing plants. Together, these results implicate AtGRP3 function root size determination during development and in Al stress

<i>AtGRP3</i> Is Implicated in Root Size and Aluminum Response Pathways in <i>Arabidopsis</i>

<div><p>AtGRP3 is a glycine-rich protein (GRP) from <i>Arabidopsis thaliana</i> shown to interact with the receptor-like kinase AtWAK1 in yeast, <i>in vitro</i> and <i>in planta</i>. In this work, phenotypic analyses using transgenic plants were performed in order to better characterize this GRP. Plants of two independent knockout alleles of <i>AtGRP3</i> develop longer roots suggesting its involvement in root size determination. Confocal microscopy analysis showed an abnormal cell division and elongation in <i>grp3-1</i> knockout mutants. Moreover, we also show that <i>grp3-1</i> exhibits an enhanced Aluminum (Al) tolerance, a feature also described in <i>AtWAK1</i> overexpressing plants. Together, these results implicate <i>AtGRP3</i> function root size determination during development and in Al stress.</p></div

Confocal analysis of root cells.

<p><b>a-c Division pattern of stele cells. * labels stele rows. a</b> Col wild-type. <b>b</b> <i>grp3-1</i> individual presenting normal division pattern. <b>c</b> <i>grp3-1</i> individual presenting abnormal division pattern. <b>d</b> Counting of number of stele cell rows. <b>e</b> Root diameter measurements. <b>f</b> Cell length measurements. <i>Error bars</i> indicate standard error. * indicates p≤ 0.05, ** indicates p≤ 0.01, *** indicates p≤ 0.005 and **** indicates p≤ 0.001.</p

Relative expression of cell elongation and/or division molecular markers in Col and <i>grp3-1</i>.

<p>Quantitative real time PCR for <b>a</b> <i>COB</i> (At5g60920). <b>b</b> <i>KOR1</i> (At5g49720). <b>c</b> <i>CESA6</i> (At5g64740). <b>d</b> <i>POM1</i> (At1g05850). <b>e</b> <i>DWF1</i> (At3g19820). <b>f</b> <i>BRI1</i> (At4g39400). <b>g</b> <i>CDC48</i> (At3g09840). <b>h</b> <i>CYCB1;2</i> (At5g06150). <i>Error bars</i> indicate standard error. * indicates p≤ 0.05, *** indicates p≤ 0.005 and **** indicates p≤ 0.001.</p

<i>grp3-1</i> loss-of-function mutant analysis.

<p><b>a</b> Relative expression of <i>AtGRP3</i> transcripts analyzed through real-time quantitative PCR of Col and <i>grp3-1</i> mutant. <b>b</b> Summarized data for root length measurements of 2-week-old plants. <i>Error bars</i> indicate standard error. *** indicates p≤ 0.005 and **** indicates p≤ 0.001.</p

Ciência, Crise e Mudança. 3.º Encontro Nacional de História das Ciências e da Tecnologia. ENHCT2012

III Encontro Nacional de História das Ciências e da Tecnologia. O Centro de Estudos de História e Filosofia da Ciência, organiza o 3.º Encontro Nacional de História da Ciência e da Técnica, sob o tema «Ciência, Crise e Mudança» que tem lugar na Universidade de Évora, nos dias 26, 27 e 28 de Setembro de 2012. O Primeiro Encontro Nacional de História da Ciência teve lugar em 21 e 22 Julho de 2009, no seguimento do programa de estímulo ao de¬senvolvimento da História da Ciência em Portugal e de valorização do património cultural e científico do País, lançado pelo Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) em 31 de Janeiro desse ano. A sua organização coube a investigadores do Instituto de História Contemporânea (IHC), da FCSH da UNL, e do Centro Científico e Cultural de Macau (CCCM), em cujas instalações se realizou. De en¬tre as conclusões do Encontro, destacou-se a de realizar periodicamen¬te novos Encontros Nacionais, a serem organizados de forma rotativa por diferentes centros e núcleos de investigadores. Na sequência deste Primeiro Encontro, o Centro Interuniversitário de História das Ciências e da Tecnologia (CIUHCT) organizou, entre 26 e 28 de Julho de 2010, o II Encontro, dedicado ao tema “Comunicação das Ciências e da Tecnologia em Portugal: Agentes, Meios e Audiências”. Cabe agora ao CEHFCi cumprir o que foi decidido no final deste Encontro. Na situação económica e política que hoje vivemos torna-se particularmente urgente aprofundar o estudo e o debate sobre a interação entre a Sociedade, a Ciência e a sua História. Coordenação Científica e Executiva do encontro estiveram a cargo de dois investigadores CEHFCi: Maria de Fátima Nunes, José Pedro Sousa Dia

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved