Merialueemme vieraslajien seurannan, varhaisvaroitus-järjestelmän (VVJ) ja riskin-arvioinnin kehittäminen

Liitteessä 1 Suomessa (Itämeressä) ns. vakiintuneet vieraslajit (useammin kuin kerran havaitut). VISEVARIS-projektin yhteydessä toimineen työryhmän ehdottamat uudet/muutetut suomenkieliset lajinimet lihavoitu. (Työryhmän vetäjänä toimi Erkki Leppäkoski).VISEVARIS-hankkeen tavoitteena oli kehittää rannikkovesiemme vieraslajien seuranta- ja varhaisvaroitusjärjestelmä (VVJ), mihin kuuluu mm. tietoisuuden lisääminen, vieraslajien aikainen havainnointi, tiedonkulun nopea välittäminen haitallisten lajien havaitsemisen jälkeen sekä kansalaisten valistaminen lajien levittämisen estämiseksi. Hankkeessa tutkittiin miltä osin ja miksi nykyseuranta ei pysty havaitsemaan uusia vieraslajeja, etsittiin tehokkaampia menetelmiä vieraslajien havaitsemiseksi ja niiden elinympäristöjen ja alueiden kartoittamiseksi, selvitettiin ja kuvattiin merialueemme keskeiset biologiset seurannat sekä niiden tuottama tieto tavattujen vieraslajien levinneisyydestä ja runsaudesta. Työssä todettiin, etteivät seurannat tavoita suurinta osaa nykyisistäkään vieraslajeista. Havaituista lajeista vain parista saadaan riittävä kuva runsauden ja levinneisyyden suhteen. Matalat rannikkovedet ovat heikoimmin seuratut elinympäristöt. Niiden seurantaa pitäisi lisätä. Hankkeessa tuotettiin ehdotus tehostetun seurannan toteuttamisesta, sen keskittämisestä eri elinympäristöihin sekä velvoiteseurannan toteuttamisesta satamissa. Hanke tuotti nettipohjaisen tunnistus-oppaan suurimmasta osasta Suomen merialueella esiintyvistä ja mahdollisesti tänne saapuvista vieraslajeista helpottamaan niiden havaitsemista ja tunnistamista. Hankkeessa selvitettiin myös vieraslajien riskinarviointiin tarjolla olevia kansainvälisiä työkaluja, joista testattaviksi valittiin makeanveden selkärangattomille kehitetty Fi-ISK ja kaloille käytetty FISK riskinarviointi-työkalu. Niiden avulla saadaan numeerisia arvoja eri lajien haitallisuudelle, mikä auttaa ryhmittelemään vieraslajeja niiden torjunnan kannalta. Kehittämällä työkaluja paremmin murtovesiolosuhteet huomioiviksi riskinarviointeja voidaan toteuttaa Itämeren alueella. Varhais-varoitus- ja informaatiojärjestelmän kehittämiseen tuotetuista osista voidaan rakentaa raamiversio, jonka kehysten sisälle tarvittava lisätieto voidaan helposti koota. Hanke auttaa kehittämään ja monipuolistamaan nykyisiä seurantoja ottamaan huomioon myös vieraslajit. Suomen kansallinen VVJ voi toimia esimerkkinä muille Itämeren maille ja se voi toimia yhteydenpitoväylänä Itämeren valtioiden kesken. Hankkeessa kehitetyllä nettilomakkeella parannetaan vieraslajihavaintojen ilmoittamismahdollisuuksia. Lomakkeen avulla niin tutkijat, konsultit, hallintoviranomaiset kuin kansalaisetkin voivat helposti ilmoittaa havaitsemansa vieraslajit sekä tarkistaa jo tehdyt vieraslajiilmoitukset. Hankkeessa saatuja tuloksia hyödynnetään EU:n meristrategia-direktiivin hyvän tilan indikaattoreita kehitettäessä sekä direktiivin toimeenpanoa tukevien seurantojen kehityksessä. Hankkeen aktiviteettien ansiosta monen vieraslajin havainnot moninkertaistuivat ja levinneisyys osoittautui oletettua laajemmaksi.Maa- ja metsätalousministeri

Cellular shape reinforces niche to stem cell signaling in the small intestine

Peer reviewe

Accumulation of Progerin Affects the Symmetry of Cell Division and Is Associated with Impaired Wnt Signaling and the Mislocalization of Nuclear Envelope Proteins

Hutchinson-Gilford progeria syndrome (HGPS) is the result of a defective form of the lamin A protein called progerin. While progerin is known to disrupt the properties of the nuclear lamina, the underlying mechanisms responsible for the pathophysiology of HGPS remain less clear. Previous studies in our laboratory have shown that progerin expression in murine epidermal basal cells results in impaired stratification and halted development of the skin. Stratification and differentiation of the epidermis is regulated by asymmetric stem cell division. Here, we show that expression of progerin impairs the ability of stem cells to maintain tissue homeostasis as a result of altered cell division. Quantification of basal skin cells showed an increase in symmetric cell division that correlated with progerin accumulation in HGPS mice. Investigation of the mechanisms underlying this phenomenon revealed a putative role of Wnt/beta-catenin signaling. Further analysis suggested an alteration in the nuclear translocation of beta-catenin involving the inner and outer nuclear membrane proteins, emerin and nesprin-2. Taken together, our results suggest a direct involvement of progerin in the transmission of Wnt signaling and normal stem cell division. These insights into the molecular mechanisms of progerin may help develop new treatment strategies for HGPS.Peer reviewe

LKB1 Destabilizes Microtubules in Myoblasts and Contributes to Myoblast Differentiation

Background: Skeletal muscle myoblast differentiation and fusion into multinucleate myotubes is associated with dramatic cytoskeletal changes. We find that microtubules in differentiated myotubes are highly stabilized, but premature microtubule stabilization blocks differentiation. Factors responsible for microtubule destabilization in myoblasts have not been identified. Findings: We find that a transient decrease in microtubule stabilization early during myoblast differentiation precedes the ultimate microtubule stabilization seen in differentiated myotubes. We report a role for the serine-threonine kinase LKB1 in both microtubule destabilization and myoblast differentiation. LKB1 overexpression reduced microtubule elongation in a Nocodazole washout assay, and LKB1 RNAi increased it, showing LKB1 destabilizes microtubule assembly in myoblasts. LKB1 levels and activity increased during myoblast differentiation, along with activation of the known LKB1 substrates AMPactivated protein kinase (AMPK) and microtubule affinity regulating kinases (MARKs). LKB1 overexpression accelerated differentiation, whereas RNAi impaired it. Conclusions: Reduced microtubule stability precedes myoblast differentiation and the associated ultimate microtubule stabilization seen in myotubes. LKB1 plays a positive role in microtubule destabilization in myoblasts and in myoblast differentiation. This work suggests a model by which LKB1-induced microtubule destabilization facilitates the cytoskeleta

Environmental cues and constraints affecting the seasonality of dominant calanoid copepods in brackish, coastal waters: a case study of Acartia, Temora and Eurytemora species in the south-west Baltic

Information on physiological rates and tolerances helps one gain a cause-and-effect understanding of the role that some environmental (bottom–up) factors play in regulating the seasonality and productivity of key species. We combined the results of laboratory experiments on reproductive success and field time series data on adult abundance to explore factors controlling the seasonality of Acartia spp., Eurytemora affinis and Temora longicornis, key copepods of brackish, coastal and temperate environments. Patterns in laboratory and field data were discussed using a metabolic framework that included the effects of ‘controlling’, ‘masking’ and ‘directive’ environmental factors. Over a 5-year period, changes in adult abundance within two south-west Baltic field sites (Kiel Fjord Pier, 54°19′89N, 10°09′06E, 12–21 psu, and North/Baltic Sea Canal NOK, 54°20′45N, 9°57′02E, 4–10 psu) were evaluated with respect to changes in temperature, salinity, day length and chlorophyll a concentration. Acartia spp. dominated the copepod assemblage at both sites (up to 16,764 and 21,771 females m−3 at NOK and Pier) and was 4 to 10 times more abundant than E. affinis (to 2,939 m−3 at NOK) and T. longicornis (to 1,959 m−3 at Pier), respectively. Species-specific salinity tolerance explains differences in adult abundance between sampling sites whereas phenological differences among species are best explained by the influence of species-specific thermal windows and prey requirements supporting survival and egg production. Multiple intrinsic and extrinsic (environmental) factors influence the production of different egg types (normal and resting), regulate life-history strategies and influence match–mismatch dynamics

Retrograde movements determine effective stem cell numbers in the intestine

The morphology and functionality of the epithelial lining differ along the intestinal tract, but tissue renewal at all sites is driven by stem cells at the base of crypts(1-3). Whether stem cell numbers and behaviour vary at different sites is unknown. Here we show using intravital microscopy that, despite similarities in the number and distribution of proliferative cells with an Lgr5 signature in mice, small intestinal crypts contain twice as many effective stem cells as large intestinal crypts. We find that, although passively displaced by a conveyor-belt-like upward movement, small intestinal cells positioned away from the crypt base can function as long-term effective stem cells owing to Wnt-dependent retrograde cellular movement. By contrast, the near absence of retrograde movement in the large intestine restricts cell repositioning, leading to a reduction in effective stem cell number. Moreover, after suppression of the retrograde movement in the small intestine, the number of effective stem cells is reduced, and the rate of monoclonal conversion of crypts is accelerated. Together, these results show that the number of effective stem cells is determined by active retrograde movement, revealing a new channel of stem cell regulation that can be experimentally and pharmacologically manipulated.Peer reviewe

Mutation analysis of three genes encoding novel LKB1-interacting proteins, BRG1, STRADα, and MO25α, in Peutz–Jeghers syndrome

Mutations in LKB1 lead to Peutz–Jeghers syndrome (PJS). However, only a subset of PJS patients harbours LKB1 mutations. We performed a mutation analysis of three genes encoding novel LKB1-interacting proteins, BRG1, STRADα, and MO25α, in 28 LKB1-negative PJS patients. No disease-causing mutations were detected in the studied genes in PJS patients from different European populations

mTORC1 in the Paneth cell niche couples intestinal stem cell function to calorie intake

How adult tissue stem and niche cells respond to the nutritional state of an organism is not well understood. Here we find that Paneth cells, a key constituent of the mammalian intestinal stem-cell (ISC) niche, augment stem-cell function in response to calorie restriction. Calorie restriction acts by reducing mechanistic target of rapamycin complex 1 (mTORC1) signalling in Paneth cells, and the ISC-enhancing effects of calorie restriction can be mimicked by rapamycin. Calorie intake regulates mTORC1 in Paneth cells, but not ISCs, and forced activation of mTORC1 in Paneth cells during calorie restriction abolishes the ISC-augmenting effects of the niche. Finally, increased expression of bone stromal antigen 1 (Bst1) in Paneth cells—an ectoenzyme that produces the paracrine factor cyclic ADP ribose—mediates the effects of calorie restriction and rapamycin on ISC function. Our findings establish that mTORC1 non-cell-autonomously regulates stem-cell self-renewal, and highlight a significant role of the mammalian intestinal niche in coupling stem-cell function to organismal physiology.National Institutes of Health (U.S.) (CA103866)National Institutes of Health (U.S.) (CA129105)David H. Koch Institute for Integrative Cancer Research at MIT (Initiator Award)Ellison Medical FoundationNational Cancer Institute (U.S.) (NCI (T32CA09216) fellowship support)Academy of FinlandFoundations’ Postdoc PoolNational Institutes of Health (U.S.) (NIH (1F32AG032833-01A1))Jane Coffin Childs Memorial Fund for Medical Researc

Eggs of the copepod Acartia tonsa Dana require hypoxic conditions to tolerate prolonged embryonic development arrest

Additional file 1. Raw data and calculations for all experiments as well as an overview of experiments in this study

Modelling ranging behaviour of female orang-utans: a case study in Tuanan, Central Kalimantan, Indonesia

Quantification of the spatial needs of individuals and populations is vitally important for management and conservation. Geographic information systems (GIS) have recently become important analytical tools in wildlife biology, improving our ability to understand animal movement patterns, especially when very large data sets are collected. This study aims at combining the field of GIS with primatology to model and analyse space-use patterns of wild orang-utans. Home ranges of female orang-utans in the Tuanan Mawas forest reserve in Central Kalimantan, Indonesia were modelled with kernel density estimation methods. Kernel results were compared with minimum convex polygon estimates, and were found to perform better, because they were less sensitive to sample size and produced more reliable estimates. Furthermore, daily travel paths were calculated from 970 complete follow days. Annual ranges for the resident females were approximately 200 ha and remained stable over several years; total home range size was estimated to be 275 ha. On average, each female shared a third of her home range with each neighbouring female. Orang-utan females in Tuanan built their night nest on average 414 m away from the morning nest, whereas average daily travel path length was 777 m. A significant effect of fruit availability on day path length was found. Sexually active females covered longer distances per day and may also temporarily expand their ranges