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51.
Photoinhibition of photosystem II in tobacco plants overexpressing glutathione reductase and poplars overexpressing superoxide dismutase 总被引:2,自引:0,他引:2
Esa Tyystjärvi Marjukka Riikonen Ana-Carolina M. Arisi Reetta Kettunen Lise Jouanin Christine H. Foyer 《Physiologia plantarum》1999,105(3):409-416
We studied photoinhibition in two cultivars of tobacco ( Nicotiana tabacum L.) expressing the bacterial gor gene in the cytosol and in four lines of poplar ( Populus tremula × P. alba ) expressing the FeSOD gene of Arabidopsis thaliana in the chloroplast. The respective total activities of glutathione reductase (EC 1.6.4.2) in leaves of gor tobaccos and superoxide dismutase (EC 1.15.1.1) in the FeSOD poplars were 5–8 times higher than in the respective untransformed control plants. Leaves of control and transformed plants were subjected to high-light stress at 20°C, and photoinhibition of photosystem II (PSII) was measured by oxygen evolution and chlorophyll fluorescence. The leaves were illuminated both in the presence and absence of lincomycin, which inhibits chloroplast protein synthesis. In both cases, the time course of loss of PSII activity was identical in plants overproducing superoxide dismutase (SOD) and in the untransformed controls, suggesting that the ability to convert superoxide to hydrogen peroxide is not a limiting factor in protection against photoinhibition, or in the repair of photoinhibitory damage or that the site of O2 − production is not accessible to the transgene product. The rate constant of photoinhibition, measured in lincomycin-treated leaves, was smaller in glutathione reductase (GR) overproducing tobacco cv. Samsun than in the respective wild-type, but this difference was not seen in cv. Bel W3. The steady-state level of PSII activity measured when the PSII repair cycle was allowed to equilibrate with photoinhibitory damage under high light was not higher in the GR overproducing cv. Samsun, suggesting that the repair of photoinhibitory damage was not enhanced in plants overproducing GR in the cytosol. 相似文献
52.
SHARPIN regulates collagen architecture and ductal outgrowth in the developing mouse mammary gland 下载免费PDF全文
Emilia Peuhu Markku Saari Camilo Guzmán Pia Rantakari Nicola De Franceschi Anni Wärri Maria Georgiadou Guillaume Jacquemet Elina Mattila Reetta Virtakoivu Yuming Liu Youmna Attieh Kathleen A Silva Timo Betz John P Sundberg Marko Salmi Marie‐Ange Deugnier Kevin W Eliceiri Johanna Ivaska 《The EMBO journal》2017,36(2):165-182
SHARPIN is a widely expressed multifunctional protein implicated in cancer, inflammation, linear ubiquitination and integrin activity inhibition; however, its contribution to epithelial homeostasis remains poorly understood. Here, we examined the role of SHARPIN in mammary gland development, a process strongly regulated by epithelial–stromal interactions. Mice lacking SHARPIN expression in all cells (Sharpincpdm), and mice with a stromal (S100a4‐Cre) deletion of Sharpin, have reduced mammary ductal outgrowth during puberty. In contrast, Sharpincpdm mammary epithelial cells transplanted in vivo into wild‐type stroma, fully repopulate the mammary gland fat pad, undergo unperturbed ductal outgrowth and terminal differentiation. Thus, SHARPIN is required in mammary gland stroma during development. Accordingly, stroma adjacent to invading mammary ducts of Sharpincpdm mice displayed reduced collagen arrangement and extracellular matrix (ECM) stiffness. Moreover, Sharpincpdm mammary gland stromal fibroblasts demonstrated defects in collagen fibre assembly, collagen contraction and degradation in vitro. Together, these data imply that SHARPIN regulates the normal invasive mammary gland branching morphogenesis in an epithelial cell extrinsic manner by controlling the organisation of the stromal ECM. 相似文献
53.
54.
Laitila A Sarlin T Kotaviita E Huttunen T Home S Wilhelmson A 《Journal of industrial microbiology & biotechnology》2007,34(11):701-713
Fusarium infection of barley and malt can cause severe problems in the malting and brewing industry. In addition to being potential
mycotoxin producers, Fusarium fungi are known to cause beer gushing (spontaneous overfoaming of beer). Cereal-derived bacteria and yeasts are potential
biocontrol agents. In this study, the antifungal potential of selected yeasts (12 strains) derived from the industrial malting
ecosystem was studied in vitro with a plate-screening assay. Several ascomycetous yeast strains showed antagonistic activity
against field and storage moulds, Pichia anomala being the most effective strain. The effects of P. anomala VTT C-04565 (C565) were examined in laboratory scale malting with naturally contaminated barley exhibiting gushing potential.
P. anomala C565 restricted Fusarium growth and hydrophobin production during malting and prevented beer gushing. Grain germination was not disturbed by the presence
of yeast. Addition of P. anomala C565 into the steeping seemed to retard wort filtration, but the filtration performance was recovered when yeast culture
was combined with Lactobacillus plantarum VTT E-78076. Well-characterized microbial cultures could be used as food-grade biocontrol agents and they offer a natural
tool for tailoring of malt properties. 相似文献
55.
Marianna Helln Arnab Bhattacharjee Riikka-Liisa Uronen Henri
J. Huttunen 《Bioscience reports》2021,41(8)
Misfolded, pathological tau protein propagates from cell to cell causing neuronal degeneration in Alzheimer’s disease and other tauopathies. The molecular mechanisms of this process have remained elusive. Unconventional secretion of tau takes place via several different routes, including direct penetration through the plasma membrane. Here, we show that tau secretion requires membrane interaction via disulphide bridge formation. Mutating residues that reduce tau interaction with membranes or formation of disulphide bridges decrease both tau secretion from cells, and penetration through artificial lipid membranes. Our results demonstrate that tau is indeed able to penetrate protein-free membranes in a process independent of active cellular processes and that both membrane interaction and disulphide bridge formation are needed for this process. QUARK-based de novo modelling of the second and third microtubule-binding repeat domains (MTBDs), in which the two cysteine residues of 4R isoforms of tau are located, supports the concept that this region of tau could form transient amphipathic helices for membrane interaction. 相似文献
56.
Reetta Hinttala Marko Kervinen Johanna Uusimaa Pilvi Maliniemi Saara Finnilä Heikki Rantala Anne M. Remes Ilmo E. Hassinen Kari Majamaa 《Mitochondrion》2010,10(4):358-361
MtDNA sequence variation is presumed to be neutral in effect, but associations with diseases and mtDNA haplogroups have been reported. The aim here was to evaluate the functional consequences of m.4216T > C present in haplogroup J. Furthermore, we evaluated m.3866T > C in MT-ND1, a variant detected in a child belonging to haplogroup J and with an isolated complex I deficiency. Homologous substitutions were introduced into Escherichia coli. NADH dehydrogenase domain activity of NDH-1 with either one or both mutations was markedly decreased suggesting that m.4216T > C and m.3866T > C may have an effect on the structural integrity of complex I. 相似文献
57.
Liisa Huttunen Pekka Niemelä Vladimir Ossipov Matti Rousi Tero Klemola 《Trees - Structure and Function》2012,26(3):809-819
Subarctic mountain birch (Betula pubescens ssp. czerepanovii) forests in northern Fennoscandia have shown a slight recovery from recent severe defoliation by the winter moth (Operophtera brumata). This development in trees is hypothesized to be a result of ameliorated growing conditions through increased summer temperatures.
We examined if accumulated thermal sum affects the ability of mountain birches to tolerate foliage losses. We quantified the
number of leaf-bearing short shoots, the emergence of inflorescences and the seasonal height growth of long shoots in both
intact and defoliated trees. We also determined the concentrations of carbon and nitrogen in leaves and carbohydrates in roots.
Our results show that defoliation constrained the growth of long shoots, as well as the emergence of inflorescences regardless
of thermal sum accumulation. However, the number of leaf-bearing short shoots did not differ between intact and defoliated
trees. In the both tree groups, the amounts of emerging leaves increased as a response to thermal sum accumulation. Also the
leaf carbon concentration increased in defoliated trees at higher thermal sums, whereas it decreased in intact controls. Generally,
the mean carbohydrate concentrations were greater in roots of defoliated than intact trees. However, with increased thermal
sums, root carbohydrates increased in intact trees but remained the same in defoliated trees. We conclude that thermal sum
accumulation does not greatly promote the recovery of mountain birches. Although the damaged trees produced more leaves at
warmer growing sites, this did not increase their height growth or carbohydrate gain in roots. 相似文献
58.
Pullinen T Mero A Huttunen P Pakarinen A Komi PV 《Journal of strength and conditioning research / National Strength & Conditioning Association》2002,16(3):383-389
Hormonal responses to an unaccustomed knee-extension exercise (E1; 5 times 10 repetitions with 40% load of 1RM [1 repetition maximum] followed by 2 sets until exhaustion) were compared in 6 men with the corresponding responses to an identical exercise performed 2 days later under the influence of delayed onset muscle soreness (DOMS) (E2). Both exercises were performed with a variable-resistance machine causing exhaustion with significantly fewer repetitions than a normal constant-resistance knee-extension device does. The E1 induced DOMS as expected, but the 1RM, the total work done, and the repetition number and frequency were not different in the 2 exercises. In the 2 sets to failure, the mean repetition number varied between 17 and 25. The exercise-induced norepinephrine, epinephrine, testosterone, cortisol (COR), and growth hormone (GH) increases were similar in the 2 exercises, although the overall level of COR and GH, including the preexercise concentrations, tended to decline in the second exercise. The results may thus suggest that the hormonal response to resistance exercise is not significantly altered when performed soon after an unaccustomed exercise bout leading to DOMS. 相似文献
59.
Human laminin M chain (merosin): complete primary structure, chromosomal assignment, and expression of the M and A chain in human fetal tissues 总被引:18,自引:5,他引:13 下载免费PDF全文
60.
Dombrowski SC Martin RP Huttunen MO 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(3):170-176
BACKGROUND: In this study, we sought to understand whether prenatal exposure to cigarette smoke would be associated with increased offspring hospitalization through age 22 years for various physical and mental health diagnoses. METHODS: We used multivariate logistic regression to investigate the relationship between gestational exposure to cigarette smoke and offspring hospitalization for physical and mental health conditions based on International Classification of Diseases (ICD; World Health Organization) diagnoses. RESULTS: When controlling for parental psychiatric status, maternal somatic health, socioeconomic status, parity, and maternal age, youth born to mothers who smoked six or more cigarettes per day were more likely to have experienced hospitalization for neuroses (OR, 1.97), diseases of the nervous system (i.e., neurological disorders) (OR, 1.47), respiratory infections (OR, 1.28), accidents (OR, 1.44), infections (OR, 1.54), undiagnosed symptoms (OR, 1.65), and total admissions (OR, 1.48). Female offspring prenatally exposed were more likely to have experienced hospitalization for obstetric complications (OR, 2.94). No association was found for the remaining categories analyzed: blood disorders, skin diseases, psychoses, metabolic/endocrine disease, circulatory disease, digestive disease, disease of the skeletal/muscular system, physical anomalies, neoplasms, and genital/urinary disease. CONCLUSIONS: This is the first study to investigate the impact of gestational exposure to cigarette smoke on global measures of somatic and physical health in offspring. This study adds to the literature by demonstrating that smoking during pregnancy increases offspring risk for additional health outcomes not previously recognized in the literature, and that the effect of smoking during pregnancy persists throughout the developmental period. The possibility that these findings are related to lifestyle markers or smoke exposure during childhood should also be considered. 相似文献