Rapid discovery of protein interactions by cell-free protein technologies

2007 ◽  
Vol 35 (5) ◽  
pp. 962-965 ◽  
Author(s):  
M. He ◽  
M.J. Taussig

Cell-free transcription and translation provides an open, controllable environment for production of correctly folded, soluble proteins and allows the rapid generation of proteins from DNA without the need for cloning. Thus it is becoming an increasingly attractive alternative to conventional in vivo expression systems, especially when parallel expression of multiple proteins is required. Through novel design and exploitation, powerful cell-free technologies of ribosome display and protein in situ arrays have been developed for in vitro production and isolation of protein-binding molecules from large libraries. These technologies can be combined for rapid detection of protein interactions.

Genetika ◽  
2004 ◽  
Vol 36 (3) ◽  
pp. 221-227
Author(s):  
Jelena Aleksic ◽  
Sasa Orlovic

Principles of the conservation of genetic resources of elms (Ulmus spp) do not differ fundamentally from the general principles accepted for the conservation of genetic resources of other common Noble Hardwoods. Efficient conservation can best be achieved through appropriate combination of in situ and ex situ methods, which have distinct advantages. Besides that, ex situ conservation is employed when emergency measures are needed for rare endangered populations and when populations are too small to be managed in situ (e.g. risks of genetic drift and inbreeding). The aim of our research is ex situ conservation of genetic resources of field elm {Ulmus minor Mill) and European white elm (Ulmus laevis Pall) through establishment of field genebanks. Sampling was conducted in one population of field elm and one population of white elm. Plant material (buds) from 8 trees of field elm and 10 trees of white elm was used for in vitro production of clones. Obtained clones will be used for establishment of field genebanks on the experimental estate of the Institute of Lowland Forestry and Environment.


2010 ◽  
Vol 22 (1) ◽  
pp. 285
Author(s):  
S. Wohlres-Viana ◽  
M. M. Pereira ◽  
A. P. Oliveira ◽  
J. H. M. Viana ◽  
M. A. Machado ◽  
...  

The Zebu breeds (Bos indicus) are different from European breeds (Bos taurus) in some aspects of their reproductive physiology, including follicle recruitment, number of follicular waves, and oocyte ultrastructure. On the other hand, embryos produced in vivo and in vitro show morphological and developmental differences, which can be related to culture environment. The aim of this study was to evaluate the effect of breed (Gyr v. Holstein) within embryo production system (in vivo and in vitro), as well as effect of production systems within breeds on relative abundance of transcripts related to formation, survival, and subsequent development of blastocysts, such as those involved in water and small solutes transport (Aquaporins 3 and 11), blastocoel formation (Na+/K+-ATPase a1 and |52), and cellular stress response (Peroxiredoxin 1). For in vivo embryo production, donors were superstimulated with FSH and inseminated, and embryos were recovered 7 days after AI. For in vitro embryo production, oocytes recovered by ovum pickup were in vitro matured and fertilized and then cultured for 7 days in culture medium under 5% CO2 at 38.5°C. For each group, blastocysts (n = 15) distributed in 3 pools were used for RNA extraction (RNeasy MicroKit, Qiagen, Valencia, CA, USA), followed by RNA amplification (Messageamp II amplification kit, Ambion-Applied Biosystems, Foster City, CA, USA) and reverse transcription (SuperScript III First-Stand Synthesis Supermix, Invitrogen, Carlsbad, CA, USA). The cDNA were submitted to real-time PCR, using the H2a gene as endogenous control, and analyzed by REST© software. To evaluate breed effect within the production systems, 2 comparisons were performed: (1) in vivo: Gyr v. Holstein and (2) in vitro: Gyr v. Holstein, considering Holstein data as 1.00. To evaluate production system effect within breeds, 2 comparisons were performed: (1) Gyr: in vivo v. in vitro and (2) Holstein: in vivo v. in vitro, considering in vivo produced embryo data as 1.00. The results are shown as mean ± SEM. For in vivo comparison between breeds, Aquaporin 3 (1.66 ± 0.77), Na+/K+-ATPase a1 (1.61 ± 0.56), and Peroxiredoxin 1 (1.61 ± 0.66) were up-regulated (P < 0.05) in Gyr embryos when compared with Holstein embryos, whereas for in vitro comparison, no differences (P > 0.05) were found. For comparisons between production systems within breeds, only Peroxiredoxin 1 (0.31 ± 0.39) was down-regulated (P < 0.01) in in vitro produced Gyr embryos when compared with in vivo counterparts. No differences (P > 0.05) were found between production systems for the Holstein breed. In conclusion, these data suggest that there is a difference on gene expression between Bos taurus and Bos indicus blastocysts, but such difference between breeds can be attenuated by the in vitro production system, indicating an embryo adaptation to the in vitro culture conditions. The data also suggest that the in vitro production system can influence the amount of transcripts in Gyr embryos. Other genes should be evaluated for a better understanding of these differences. Financial support was provided by CNPq and FAPEMIG.


2017 ◽  
Vol 1 (1) ◽  
pp. 20-28 ◽  
Author(s):  
Amir Mehdizadeh ◽  
Masoud Darabi

A large number of patients are affected by liver dysfunction worldwide. Liver transplantation is the only efficient treatment in a variety of enduring liver disorders including inherent and end-stage liver diseases. The generation of human functional hepatocytes in high quantities for liver cell therapy is an important goal for ongoing therapies in regenerative medicine. Reprogrammed cells are considered as a promising and unlimited source of hepatocytes, mainly because of their expected lack of immunogenicity and minimized ethical concerns in clinical applications. Despite gained advances in the reprogramming of somatic cells to functional hepatocytes in vitro, production of primary adult hepatocytes that can proliferate in vivo still remains inaccessible. As part of efforts toward translation of cell reprogramming science into clinical practice, more careful cell selection strategies should be integrated into improvement of dedifferentiation and redifferentiation protocols, especially in precision medicine where gene correction is needed. Furthermore, advances in cellular reprogramming highlight the need for developing and evaluating novel standards addressing clinical research interests in this field.


2021 ◽  
Vol 5 (10) ◽  
pp. 2490-2504
Author(s):  
Raymond Liang ◽  
Vijay Menon ◽  
Jiajing Qiu ◽  
Tasleem Arif ◽  
Santosh Renuse ◽  
...  

Abstract Mammalian red blood cells (RBCs), which primarily contain hemoglobin, exemplify an elaborate maturation process, with the terminal steps of RBC generation involving extensive cellular remodeling. This encompasses alterations of cellular content through distinct stages of erythroblast maturation that result in the expulsion of the nucleus (enucleation) followed by the loss of mitochondria and all other organelles and a transition to anaerobic glycolysis. Whether there is any link between erythroid removal of the nucleus and the function of any other organelle, including mitochondria, remains unknown. Here we demonstrate that mitochondria are key to nuclear clearance. Using live and confocal microscopy and high-throughput single-cell imaging, we show that before nuclear polarization, mitochondria progressively move toward one side of maturing erythroblasts and aggregate near the nucleus as it extrudes from the cell, a prerequisite for enucleation to proceed. Although we found active mitochondrial respiration is required for nuclear expulsion, levels of mitochondrial activity identify distinct functional subpopulations, because terminally maturing erythroblasts with low relative to high mitochondrial membrane potential are at a later stage of maturation, contain greatly condensed nuclei with reduced open chromatin–associated acetylation histone marks, and exhibit higher enucleation rates. Lastly, to our surprise, we found that late-stage erythroblasts sustain mitochondrial metabolism and subsequent enucleation, primarily through pyruvate but independent of in situ glycolysis. These findings demonstrate the critical but unanticipated functions of mitochondria during the erythroblast enucleation process. They are also relevant to the in vitro production of RBCs as well as to disorders of the erythroid lineage.


2019 ◽  
Vol 31 (1) ◽  
pp. 168
Author(s):  
B. H. Bernal ◽  
J. L. Barajas ◽  
J. A. Ortega ◽  
A. Cedeño ◽  
S. Andrada ◽  
...  

A retrospective analysis of embryo production records from 2013 to 2017 was carried out to evaluate the in vivo and in vitro production (IVP) of embryos in donors of the Bonsmara breed (i.e. tropically adapted Bos taurus). Only donors with production records of both in vivo and in vitro embryos during the same period were used. A total of 127 superovulations and ova/embryo collections of 19 donors were evaluated. The donors were superstimulated with the following protocol: on Day 0 they received a device with 1g of progesterone (DIB, Zoetis, Argentina), 50mg of rogesterone (Progestar, Zoetis), and 5mg of oestradiol-17β (17ßOestradiol, Rio de Janeiro, Argentina) or 2mg of oestradiol benzoate (Gonadiol, Zoetis) intramuscularly (IM) at the same time. Superstimulatory treatments were initiated on the morning of Day 4 with Folltropin-V (Vetoquinol, France; total dose=240 to 340mg IM) in twice-daily decreasing doses over 4 days. All donors received 2 IM injections of 500µg of cloprostenol (Ciclase DL, Zoetis) on the morning and afternoon of Day 6 and; the intravaginal devices were removed on the morning of Day 7 and 100µg of Gonadorelin (gonadotropin-releasing hormone, Gonasyn gdr, Zoetis) was given on the morning of Day 8. Donors were inseminated using semen from 9 Bonsmara bulls, 12 and 24h after gonadotropin-releasing hormone. On Day 15, ova/embryos were collected and classified according to IETS standards. A total of 89 follicular aspirations (ovum pickup) of 19 donors for IVP were evaluated. The ovum pickups were performed at random stages of oestrous cycle, without superstimulation or other hormone treatments. A total of 1109 viable oocytes (12.5±0.9 per ovum pickup) were collected and matured for 24h in 100-µL drops of maturation medium (TCM-199, supplemented with hormones) under mineral oil and incubated at 38.5°C in 5.5% CO2 and humidity at saturation. Fertilization was performed using 3 Bonsmara bulls that were also used for in vivo embryo production. Viable sperm were obtained using the percoll gradient technique (45-90%). The sperm pellet was dissolved in TL-Sperm, centrifuged, and then diluted to a final concentration of 1.5×106 sperm/mL. Zygotes were stripped and placed in drops of 100µL of SOF medium supplemented with 0.4% BSA under oil at 38.8°C, 5.5% CO2, 7% O2, and humidity at saturation for 7 days. The culture medium was renewed on Days 3 and 5. The data were analysed using the GLM procedure of SAS (SAS Institute Inc., Cary, NC, USA), a P-value &lt;0.05 was considered significant. The mean (±standard error of the means) number of CL, ova/embryos collected, fertilized ova, and transferable embryos were 12.9±0.6, 8.8±0.6, 6.6±0.5, and 4.7±0.4, respectively. A total of 662 oocytes (66.3±2.4%) cleaved 48h post-IVF. On Day 7, an average of 4.4±0.3 embryos were produced. No differences were detected in the number of transferable embryos produced in vivo v. those produced in vitro. Furthermore, no significant differences were found between the techniques or bulls on the proportion of embryos produced in relation to the ova/embryos or oocytes obtained (in vivo 51.5±3.2% v. in vitro 42.9±2.5%). In conclusion, the in vivo and in vitro production of embryos are both effective alternatives to increase the number of offspring from valuable Bonsmara donors.


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