Guidelines
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LABORATORY PROCEDURES FOR GENOMIC LIBRARIES
REFERENCE NO: GLI/1998/3/7 TITLE: PRODUCTION OF HIGH DENSITY GRIDDED PAC/FUGU FILTERS For agar plates Bioassay plates [Nunc 166508 for PBA][Q-tray for Qbot] PBA robot + 384 pin gridding head/orQbot + 384 pin gridding head Perspex trays PBA: 30 agar plates are poured on Fridays, for gridding runs on the following Monday and Tuesday. 24 plates are needed for each days gridding. If the agar has been received from the Sanger kitchens before it has set, place the bottles directly in the hybridising oven at 65oC. Otherwise microwave the 500ml bottles of LB agar. Make sure that the agar does not spill over in the microwave. The melted agar can be stored in a hybridising oven at 65oC until ready to be poured. Only open the sterile Bioassay plates within the open fronted safety cabinet (sterile hood) in B310. The hood should have been sprayed with alcohol before use. Always pour 1 - 2 extra plates each time as spares to use if there are problems. Store the plates, wrapped in clingfilm, upside-down, in the fridge until required.
Laying on the Hybond N paper Work in a laminar flow cabinet, the 'hood', to lay the Hybond N filters on the agar. L a b e l Use the sterile flamed blue-handled tweezers to lift each membrane and place on the surface of the agar. The membrane must be laid absolutely flat, with no air bubbles underneath. (the PAC library has no plates labelled 174, 175, 176, 284, 285 and 311). These positions are replaced during gridding with empty sterile plates) Remove the 384 well plates to be gridded from the freezer in B309 with the gridding copy of the library: PAC = L56 Lay the frozen plates on an alcohol cleaned bench to thaw completely before gridding. Select PBA Flexys Bioassay Gridder [double click mouse] The tool head will move NEWPAC program (for all filters, both PAC and Fugu, that have 48 input plates) Remove the 384 pin tool from the drying cabinet, and when cool load carefully onto the robot arm. The tool must be pushed right to the back and the retaining clip pushed across to hold the tool securely. The front of the tool will be flush with the robot arm when the tool is fitted correctly. x x x Filter 1 Filter 2 Filter 3 Plate 1 Plate 2 Plate 3 Plate 4 Plate 5 Heater Plate 6 Plate 7 Plate 8 Plate 9 Plate 10 EtOH Dry the tops of the 384 well source plates before stacking in groups of 5. So each time source plates are changed during the gridding run, two groups of 5 plates will be taken off, and the next consecutive two groups of five plates will be loaded. When everything is set up: Start gridding [click on box] bioassay plate patch 1 If it does click on OK Gridding will start Gridding will resume When all 48 source plates have been gridded the first 3 filters have been prepared. Load the next three bioassay plates on the gridder and start the gridding run again. After gridding replace the source plates in their freezer trays and place on an empty shelf in one of the freezers. Next day return these frozen trays to their correct positions in the gridding freezer. At the end of the day (as late as possible) place the plates in the 37oC incubator. They should be incubated only in stacks of three, and should remain wrapped in clingfilm and upside down. Incubation should be for 12 hours, but overnight is longer than that - so remove from the incubator first thing in the morning. Close down the PBA by exiting from the program and exiting windows. Switch off the Gridder, computer, screen controlled air supply and heater at the wall switches. Carefully take the 384 pin tool off the robot. Carry the tool, in its plastic trough, to the sonicating water bath. The bath should be filled to the line with distilled water and a drop or so of detergent (Decon 90). Carefully place the tool in the clamp, and after making sure it is clamped securely, lower it into the sonicating bath, until the shafts of the pins are submerged (but not the heads of the pins). The pins should not touch the bottom. Now the bath can be switched on, front bottom RHS. Set the time to ten minutes by first pressing the clock icon, then enter "10" and finally press the icon to the left of the numerals (a vertical line in a circle). The orange indicator light shows that the bath is now sonicating. DO NOT PLACE HANDS IN THE WATER OF A SONICATOR! After the 10 minutes are finished, switch the bath off, raise the tool and empty the water. This can be done by scooping the water out, or by using the siphon, and finishing by mopping up the water with paper towels. Now fill the bath with distilled water only, lower the tool back in, and sonicate for another 10 minutes. At the end of this the bath is switched off, and the tool lifted out. Very carefully shake the tool to get rid of excess water. Now drench the tool using absolute alcohol in a wash bottle over the sink. Shake the tool again, and place in the robot to dry overnight. There are three plates in the cFugu library left over when the gridding onto large filters has finished. These plates are gridded onto small Hybond N+ filters on Hybaid colony picking plates. cFugu 5 are gridded on the same day as cFugu 4, as they only take a short time to grid. The solid bioassay base plates in the PBA are removed, and replaced be the gridding support base plates. The PBA program to be selected is: PBA Flexys Gridder Robot arrangement: Source Plates Agar Plates 197 198 199 Heater EtOH Load the 3 source plates into the rack. It is very important that the plates are clipped fully into the rack. When the rack is placed on the LHS position in the robot, check all plates are correctly loaded, by looking at them at eye level. An incorrectly placed plate will be higher than the correctly placed ones. Load the first 8 destination plates plate, with the Hybond membrane onto the second rack. These colony picking plates are larger than the 96-well plates and are much stiffer fitting into the racks. But it is essential that they are fully seated in the rack, otherwise they may move during gridding and the gridded filter pattern will be very haphazard. Carefully remove the lids from the trays, placing them on the black plastic base on the LHS in the robot. Remove the lids starting with the plates furthest away, to avoid putting your arms over the open plates (and replace the lids, after gridding, in the opposite order). Remove the lid from the agar destination plate. Shut the door. Start the programme. The 16 agar plates are incubated upside down, wrapped in clingfilm exactly as the large filters. PLEASE RECORD THE DATE OF EACH GRIDDING ON THE RECORD SHEET PINNED TO THE SIDE OF THE PBA GRIDDER PLEASE RECORD THE DATE OF EACH GRIDDING, FILTER SET, NUMBER OF FILTERS GRIDDED AND HYBOND MEMBRANE BATCH NUMBER IN THE FILTER RECORD BOOK. All the large filters we produce are double spotted. This means that every plate is spotted twice onto the filter, in a set position. So a user will always get two spots come up for a positive hybridisation signal. The purpose of this is so that two spots makes very clear that the positive is really positive, and the gridding arrangement is such that each double spot has a distinctive orientation - making it very easy for the user to correctly identify the positive clone. The spotting pattern is: Please do not attempt to alter, or even check, the gridding arrangement in the PBA NEWPAC programme, as there is a fault in the software, which can lead to inadvertent erasure of the pattern. Gridding using the Genetix Qbot follows exactly the same principles as with the PBA Gridder - the main difference being that 24 filters can be gridded in a day leaving the operator time to pour out plates and lay filters for the following day. Thaw out source plates When the source plates are thawed gently wipe the tops of the lids. If the lids are wet this will interfere with the lid lifter. Load the hotel: Hotel 1 Hotel 2 1 10 19 28 37 46 2 11 20 29 38 47 3 12 21 30 39 48 4 13 22 31 40 5 14 23 32 41 6 15 24 33 42 7 16 25 34 43 8 17 26 35 44 9 18 27 36 45 Plates fit into the hotel with well A1 facing the open front of the hotel, and the labels showing. Make sure that the plates are loaded in the correct order. Layout of the Qbot "floor" ** ** ** Alcohol 10 11 12 Brush bath Heater ** ** ** 7 8 9 ** ** ** 4 5 6 Plate ** ** ** Holder Sucker 1 2 3 A1 A1 Hotel 2 Hotel 1 FRONT OF QBOT Computer Switch on the compressor at the wall Flick on the red and yellow button on the front LHS of the Qbot. This will activate the computer. In Program Manager - open the window for 'Genetix Qbot' For gridding select 'Genetix Gridder' and click OK The message "Initialising Drives - Make sure main power is on" will be displayed Click OK The "Make sure all doors are closed" prompt will appear (the robot will not work with the doors open) Gridding number Complete and click on 'gridding' box to proceed Display now shows "Gridding Routine Set-up": Start-up Settings: Sterilising Set-up: Additional options: Gridding speed - fast Gridding pin adjustment on filters - This should stay on "no change" (as this has already been set up in the config. Option) When ready click on "Run" Message will read "Make sure clamps are on" Click OK The run will now start - and will take approx. 2hrs 35min. At the end of the first run, replace the lids on the Q trays and remove them. Fit the second batch of Q trays and remove their lids. Click on "Close" and Quit from the "Genetix Sign On" screen Switch off - by pressing the red button on the robot Turn the big red and yellow switch to OFF Switch compressor off at the wall Remove the Sterilising Bath and empty out the alcohol Remove the 15/24 agar plates from the incubator 1. 10% SDS Place 3MM paper, cut to size, in the large perspex trays. Add the SDS and thoroughly wet the 3MM paper. Tip off the excess SDS. After tipping off the excess roll the 3MM paper with a 5ml plastic pipette to ensure that the 3MM is flat. It is critical that the 3MM paper is evenly wet - however it is also critical that it is neither too wet nor too dry. Only practice will help determine the correct degree of wetness. Too wet = colonies will merge and create a "dulux" appearance. Too dry = colonies will not bind to the membrane. This step stops the colonies spreading and starts lysing the E.coli. 2. Blotting As you lift off the membrane to transfer it to the next perspex tray, briefly lay the membrane onto clean dry 3MM paper to blot off much of the SDS, and thus reduce bubble problems at the next stage. 3. 0.5M NaOH/1.5M NaCl Make up 4 perspex trays with 3MM paper soaked in 0.5M NaOH/1.5M NaCl exactly as described in step one. Lift each membrane off the SDS, blot, and transfer to this NaOH/NaCl tray. 4. Air dry Lift each membrane off the 3MM paper and lay on clean dry 3MM paper Box 1 0.5M Tris pH 7.4/1.5M NaCl 50mM Tris pH 7.4/ 0.15M NaCl 2xSSC Box 2 0.5M Tris pH 7.4/1.5M NaCl 2xSSC/0.1% SDS 50mM Tris pH 7.4 From now on you will be transferring filters from box 1 to box 2 to box 1 etc. All the transfers will usually be in batches of 8 5. 0.5M Tris pH 7.4/ 1.5M NaCl Lift each membrane off the 3MM paper and place in box 1, making sure that each membrane is fully submerged. 6. 0.5M Tris pH 7.4/1.5M NaCl Lift each membrane from box 1 and place in box 2, making sure that each membrane is fully submerged. 7. 50mM Tris pH 7.4/0.15M NaCl This is 1/10 neutralising solution 8. 2xSSC/0.1% SDS Lift each membrane from box 1 and place in box 2, making sure that each membrane is fully submerged. 9. 2xSSC Lift each membrane from box 2 and place in box 1, making sure that each membrane is fully submerged. 10. 50mM Tris pH 7.4 Lift each membrane from box 1 and place in box 2, making sure that each membrane is fully submerged. 11. Air Dry Take each filter out and lay on clean dry 3MM paper. At the end of the day cover with a sheet of 3MM paper so that dust does not land on the filters (but make sure that the filters are dry before you do this). 12. Crosslinking Each filter is placed in the crosslinker individually. Select "optimal" and press start Place the filters into a clean ziplock plastic bag. Write on the filter number, the date and the QA code of the filter .This code should also be entered in the filter record book. 10% SDS 100g SDS to 1 L with MilliQ 0.5M NaOH/1.5M NaCl NaOH 20g NaCl 87.7g to I L with MilliQ - Make up fresh on the day of processing 0.5M Tris pH 7.4/1.5M NaCl NaCl 438.5g Tris 303g 50mM Tris pH 7.4/ 0.15M NaCl This is a 1 in 10 dilution of the buffer above Tri Sodium Citrate 88.2g NaCl 175.3g to 1 L with MilliQ. Stir to dissolve. Autoclave 100ml of 20xSSC 10ml of 10% SDS Made up to 1 L with MilliQ
2xSSC 1L of 20xSSC Made up to 10 L with MilliQ 1M Tris/HCl pH 7.4 Tris 121.1g This is a 1 in 20 dilution of the buffer above [= 250ml of 1M stock + 4750ml MilliQ to make 5L final volume] Records are kept of all filters made - so that if any user has a problem with a set of filters, we can look at the records and establish if there were any clues as to what may have gone wrong. When handling the filters wear gloves When the batch of filters have been cross-linked they are placed in ziplock bags, with the filter batch number and the filter number (i.e. Fugu 3) labelled on the outside of the bag. In the black record book details should have been entered in the first section called "Filter Production". Making up filter sets There are two parts to this: Take the filters out of the bag and examine very closely to establish good (OK) and not so good (NSG) filters. Good filters - should clearly show the 16 individual spots at each position. NSG filters - Divide the filters into good and NSG - and record this number in the record book The filters are usually replaced in the ziplock bag, between two sheets of 3MM paper, with the good and NSG placed back to back, with 3MM in-between, clearly labelled with good and number of good filters written on the 3MM paper on one side, and NSG and number of NSG filters written on the 3MM paper on the underside of the bag. Score all the filters like this. Only use the good filters. PAC library = Filters 1 - 7 The number of complete sets that can be made will be determined by the filter which has the lowest number of usable good filters. Each set is placed in a ziplock bag and labelled with the Filter set number. Before the sets are put away in storage, another member of the group must check each set to make sure that it is complete, containing the correct number of filters and that no filter is duplicated. Several of the bags of individual filters will still have good filters remaining. Correct the number of good filters on the bag label. A separate record sheet is kept of this number of good filters remaining, but not yet in sets, and this helps us determine which filters to grid next. the date sent out Guidelines prepared for CABRI by HGMP, December 1998
© The CABRI Consortium 1999 -
2023
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