Compatibility Relationships in \u27Tugarka\u27 Sweet Cherry (Prunus avium L.)

\u27Tugarka\u27 je najzastupljenija sorta trešnje u mediteranskom dijelu Hrvatske. Jedan od uzroka njene neredovite rodnosti je loš uspjeh oprašivanja s inkompatibilnim sortama prisutnim u nasadima. Analizirana je uspješnost zametanja plodova nakon samooprašivanja, stranooprašivanja i slobodnog oprašivanja sorte Tugarka, te su izdvojeni njeni najbolji oprašivači. U ulozi oprašivača, u istraživanje su uključene sorte Lambert compact, Bing spur, Van compact i višnja maraska \u27Poljička\u27, koje su istovremeno cvjetale sa glavnom istraživanom sortom. Uspjeh klijavosti polena analiziran je metodom viseće kapi u 12% otopini saharoze pri temperaturi od 22ºC. Klijavost polena sorti oprašivača zabilježena je u rasponu od 35% (\u27Van compact\u27) do 41.04% (\u27Bing spur\u27). Zbog izostanka zametanja plodova nakon samooprašivanja \u27Tugarka\u27 je opisana kao autoinkompatibilna sorta. Značajno najveći uspjeh zametanja plodova kod sorte Tugarka zabilježen je nakon oprašivanja sa sortom Lambert compact (22.5%), a najmanji nakon oprašivanja sa višnjom maraskom \u27Poljička\u27 (14.2%).\u27Tugarka\u27 is most presented cultivar grown in orchards of Mediterranean part of Croatia. Inadequate pollination caused irregular yield of that valuable cultivar. The aim of this study was to determinate the success of self-pollination, cross-pollination and free-pollination of \u27Tugarka\u27, and to define its best pollenizer(s). Cultivars used as pollen donors, \u27Lambert compact\u27, \u27Bing spur\u27, \u27Van compact\u27, and sour cherry marasca \u27Poljička\u27, were selected according to their simultaneous flowering period with \u27Tugarka\u27. Pollen germination of tested cultivars was determined in 12% sucrose solution at 22ºC using hanging drop technique. Controlled pollinations with pollen of each pollenizer were carried out during the full bloom. Fruit set following selfpollination, cross-pollination and free-pollination was analysed just before the harvest. Pollen germination rates varied from 35% (\u27Van compact\u27) to 41.04% (\u27Bing spur\u27). Absence of fruit set following self-pollination described \u27Tugarka\u27 as self-incompatible cultivar. Significantly the best fruit set of \u27Tugarka\u27 was recorded after the pollination with \u27Lambert compact\u27 (22.5%), and the lowest following pollination with sour cherry \u27Poljička\u27 (14.2%)

Compatibility Relationships in \u27Tugarka\u27 Sweet Cherry (Prunus avium L.)

\u27Tugarka\u27 je najzastupljenija sorta trešnje u mediteranskom dijelu Hrvatske. Jedan od uzroka njene neredovite rodnosti je loš uspjeh oprašivanja s inkompatibilnim sortama prisutnim u nasadima. Analizirana je uspješnost zametanja plodova nakon samooprašivanja, stranooprašivanja i slobodnog oprašivanja sorte Tugarka, te su izdvojeni njeni najbolji oprašivači. U ulozi oprašivača, u istraživanje su uključene sorte Lambert compact, Bing spur, Van compact i višnja maraska \u27Poljička\u27, koje su istovremeno cvjetale sa glavnom istraživanom sortom. Uspjeh klijavosti polena analiziran je metodom viseće kapi u 12% otopini saharoze pri temperaturi od 22ºC. Klijavost polena sorti oprašivača zabilježena je u rasponu od 35% (\u27Van compact\u27) do 41.04% (\u27Bing spur\u27). Zbog izostanka zametanja plodova nakon samooprašivanja \u27Tugarka\u27 je opisana kao autoinkompatibilna sorta. Značajno najveći uspjeh zametanja plodova kod sorte Tugarka zabilježen je nakon oprašivanja sa sortom Lambert compact (22.5%), a najmanji nakon oprašivanja sa višnjom maraskom \u27Poljička\u27 (14.2%).\u27Tugarka\u27 is most presented cultivar grown in orchards of Mediterranean part of Croatia. Inadequate pollination caused irregular yield of that valuable cultivar. The aim of this study was to determinate the success of self-pollination, cross-pollination and free-pollination of \u27Tugarka\u27, and to define its best pollenizer(s). Cultivars used as pollen donors, \u27Lambert compact\u27, \u27Bing spur\u27, \u27Van compact\u27, and sour cherry marasca \u27Poljička\u27, were selected according to their simultaneous flowering period with \u27Tugarka\u27. Pollen germination of tested cultivars was determined in 12% sucrose solution at 22ºC using hanging drop technique. Controlled pollinations with pollen of each pollenizer were carried out during the full bloom. Fruit set following selfpollination, cross-pollination and free-pollination was analysed just before the harvest. Pollen germination rates varied from 35% (\u27Van compact\u27) to 41.04% (\u27Bing spur\u27). Absence of fruit set following self-pollination described \u27Tugarka\u27 as self-incompatible cultivar. Significantly the best fruit set of \u27Tugarka\u27 was recorded after the pollination with \u27Lambert compact\u27 (22.5%), and the lowest following pollination with sour cherry \u27Poljička\u27 (14.2%)

The Bloom's syndrome helicase (BLM) interacts physically and functionally with p12, the smallest subunit of human DNA polymerase δ

Bloom's syndrome (BS) is a cancer predisposition disorder caused by mutation of the BLM gene, encoding a member of the RecQ helicase family. Although the phenotype of BS cells is suggestive of a role for BLM in repair of stalled or damaged replication forks, thus far there has been no direct evidence that BLM associates with any of the three human replicative DNA polymerases. Here, we show that BLM interacts specifically in vitro and in vivo with p12, the smallest subunit of human POL δ (hPOL δ). The hPOL δ enzyme, as well as the isolated p12 subunit, stimulates the DNA helicase activity of BLM. Conversely, BLM stimulates hPOL δ strand displacement activity. Our results provide the first functional link between BLM and the replicative machinery in human cells, and suggest that BLM might be recruited to sites of disrupted replication through an interaction with hPOL δ. Finally, our data also define a novel role for the poorly characterized p12 subunit of hPOL δ

Hereditary leiomyomatosis and renal cell cancer presenting as metastatic kidney cancer at 18 years of age: implications for surveillance

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant syndrome characterized by skin piloleiomyomas, uterine leiomyomas and papillary type 2 renal cancer caused by germline mutations in the fumarate hydratase (FH) gene. Previously, we proposed renal imaging for FH mutation carriers starting at the age of 20 years. However, recently an 18-year-old woman from a Dutch family with HLRCC presented with metastatic renal cancer. We describe the patient and family data, evaluate current evidence on renal cancer risk and surveillance in HLRCC and consider the advantages and disadvantages of starting surveillance for renal cancer in childhood. We also discuss the targeted therapies administered to our patient

Oxygen Consumption Can Regulate the Growth of Tumors, a New Perspective on the Warburg Effect

The unique metabolism of tumors was described many years ago by Otto Warburg, who identified tumor cells with increased glycolysis and decreased mitochondrial activity. However, "aerobic glycolysis" generates fewer ATP per glucose molecule than mitochondrial oxidative phosphorylation, so in terms of energy production, it is unclear how increasing a less efficient process provides tumors with a growth advantage.We carried out a screen for loss of genetic elements in pancreatic tumor cells that accelerated their growth as tumors, and identified mitochondrial ribosomal protein L28 (MRPL28). Knockdown of MRPL28 in these cells decreased mitochondrial activity, and increased glycolysis, but paradoxically, decreased cellular growth in vitro. Following Warburg's observations, this mutation causes decreased mitochondrial function, compensatory increase in glycolysis and accelerated growth in vivo. Likewise, knockdown of either mitochondrial ribosomal protein L12 (MRPL12) or cytochrome oxidase had a similar effect. Conversely, expression of the mitochondrial uncoupling protein 1 (UCP1) increased oxygen consumption and decreased tumor growth. Finally, treatment of tumor bearing animals with dichloroacetate (DCA) increased pyruvate consumption in the mitochondria, increased total oxygen consumption, increased tumor hypoxia and slowed tumor growth.We interpret these findings to show that non-oncogenic genetic changes that alter mitochondrial metabolism can regulate tumor growth through modulation of the consumption of oxygen, which appears to be a rate limiting substrate for tumor proliferation

Primary Coenzyme Q Deficiency in Pdss2 Mutant Mice Causes Isolated Renal Disease

Coenzyme Q (CoQ) is an essential electron carrier in the respiratory chain whose deficiency has been implicated in a wide variety of human mitochondrial disease manifestations. Its multi-step biosynthesis involves production of polyisoprenoid diphosphate in a reaction that requires the enzymes be encoded by PDSS1 and PDSS2. Homozygous mutations in either of these genes, in humans, lead to severe neuromuscular disease, with nephrotic syndrome seen in PDSS2 deficiency. We now show that a presumed autoimmune kidney disease in mice with the missense Pdss2kd/kd genotype can be attributed to a mitochondrial CoQ biosynthetic defect. Levels of CoQ9 and CoQ10 in kidney homogenates from B6.Pdss2kd/kd mutants were significantly lower than those in B6 control mice. Disease manifestations originate specifically in glomerular podocytes, as renal disease is seen in Podocin/cre,Pdss2loxP/loxP knockout mice but not in conditional knockouts targeted to renal tubular epithelium, monocytes, or hepatocytes. Liver-conditional B6.Alb/cre,Pdss2loxP/loxP knockout mice have no overt disease despite demonstration that their livers have undetectable CoQ9 levels, impaired respiratory capacity, and significantly altered intermediary metabolism as evidenced by transcriptional profiling and amino acid quantitation. These data suggest that disease manifestations of CoQ deficiency relate to tissue-specific respiratory capacity thresholds, with glomerular podocytes displaying the greatest sensitivity to Pdss2 impairment

Lentivirus-meditated frataxin gene delivery reverses genome instability in Friedreich ataxia patient and mouse model fibroblasts

Friedreich ataxia (FRDA) is a progressive neurodegenerative disease caused by deficiency of frataxin protein, with the primary sites of pathology being the large sensory neurons of the dorsal root ganglia and the cerebellum. FRDA is also often accompanied by severe cardiomyopathy and diabetes mellitus. Frataxin is important in mitochondrial iron–sulfur cluster (ISC) biogenesis and low-frataxin expression is due to a GAA repeat expansion in intron 1 of the FXN gene. FRDA cells are genomically unstable, with increased levels of reactive oxygen species and sensitivity to oxidative stress. Here we report the identification of elevated levels of DNA double strand breaks (DSBs) in FRDA patient and YG8sR FRDA mouse model fibroblasts compared to normal fibroblasts. Using lentivirus FXN gene delivery to FRDA patient and YG8sR cells, we obtained long-term overexpression of FXN mRNA and frataxin protein levels with reduced DSB levels towards normal. Furthermore, γ-irradiation of FRDA patient and YG8sR cells revealed impaired DSB repair that was recovered on FXN gene transfer. This suggests that frataxin may be involved in DSB repair, either directly by an unknown mechanism, or indirectly via ISC biogenesis for DNA repair enzymes, which may be essential for the prevention of neurodegeneration.Ataxia UK, FARA Australasia and FARA US

The Warburg Effect Is Genetically Determined in Inherited Pheochromocytomas

The Warburg effect describes how cancer cells down-regulate their aerobic respiration and preferentially use glycolysis to generate energy. To evaluate the link between hypoxia and Warburg effect, we studied mitochondrial electron transport, angiogenesis and glycolysis in pheochromocytomas induced by germ-line mutations in VHL, RET, NF1 and SDH genes. SDH and VHL gene mutations have been shown to lead to the activation of hypoxic response, even in normoxic conditions, a process now referred to as pseudohypoxia. We observed a decrease in electron transport protein expression and activity, associated with increased angiogenesis in SDH- and VHL-related, pseudohypoxic tumors, while stimulation of glycolysis was solely observed in VHL tumors. Moreover, microarray analyses revealed that expression of genes involved in these metabolic pathways is an efficient tool for classification of pheochromocytomas in accordance with the predisposition gene mutated. Our data suggest an unexpected association between pseudohypoxia and loss of p53, which leads to a distinct Warburg effect in VHL-related pheochromocytomas