Tariq Javeed

Questions and Answers (8) View all

• Answer added in Plant Nematology
  1 Please can I have the websites of the listed Nematological Societies?
  By Ayodele Adegbite · Institute of Agricultural Research & Training
  Tariq Javeed · King Saud University

  Yes offcourse these all societies have their own websites you can find! 

  Yes offcourse these all societies have their own websites you can find!
  Following
• Answer added in Plant Nematology
  5 how to save nematode(C. elegans) in -80℃?
  By Mei Mei · Chinese Academy of Agricultural Sciences
  Tariq Javeed · King Saud University

  You welcome..... 

  You welcome.....
  Following
• Answer added in Plant Nematology
  5 how to save nematode(C. elegans) in -80℃?
  By Mei Mei · Chinese Academy of Agricultural Sciences
  Tariq Javeed · King Saud University

  you may read full article how to save C. elegans its very helpful! http://www.wormbook.org/chapters/www_strainmaintain/strainmaintain.html 

  you may read full article how to save C. elegans its very helpful! http://www.wormbook.org/chapters/www_strainmaintain/strainmaintain.html
  Following
• Answer added in Plant Nematology
  5 how to save nematode(C. elegans) in -80℃?
  By Mei Mei · Chinese Academy of Agricultural Sciences
  Tariq Javeed · King Saud University

  ok you can save that follow that protocol! Freezing and recovery of C. elegans stocks Caenorhabditis elegans can be frozen and stored indefinitely... [more]

  ok you can save that follow that protocol! Freezing and recovery of C. elegans stocks Caenorhabditis elegans can be frozen and stored indefinitely in liquid nitrogen (−196 °C) (Brenner, 1974). The keys to a successful freeze are using animals at the correct stage of development, the addition of glycerol to the freezing media, and a gradual cooling to -80°C. Freshly starved young larvae (L1-L2 stage) survive freezing best. Well-fed animals, adults, eggs and dauers do not survive well. It is best to use several plates of worms that have just exhausted the E. coli OP50 lawn and that contain lots of L1-L2 animals. A 15% final volume of glycerol in the freezing solution is used. A 1°C decrease in temperature per minute is desirable during freezing. This can be achieved by placing the worms (in freezer vials) in a styrofoam container at -80°C. The styrofoam container can be either a commercial shipping box (with walls at least ¾ inch thick) or a small styrofoam box with slots for holding vials. After 12 or more hours at -80°C, the freezer vials should be transferred to their permanent freezer location for long term storage. The CGC uses two solutions for freezing C. elegans: a Liquid Freezing Solution (Brenner, 1974) and Soft Agar Freezing Solution (Leon Avery, personal communication). For long term storage of stocks in liquid nitrogen, Liquid Freezing Solution is recommended. When this solution is used, the worms settle to the bottom of the freezer vial, and no viable animals can be easily retrieved without thawing the entire contents of the vial. A Soft Agar Freezing Solution is useful for freezing working stocks of C. elegans. The addition of the agar helps keep the worms suspended throughout the solution. A small scoop of the frozen contents can be taken, and the remainder can be left in the vial and returned to the freezer for later use. Vials frozen using Soft Agar Freezing Solution should be stored at -80°C. If kept in liquid nitrogen, the contents become too hard, and the vial will need to be warmed before it is possible to remove a scoop of the contents. The warming period reduces the number of times live worms can be recovered from the vial. When stored at -80°C there is no need to allow the vial to be warmed; the contents are soft enough to be used right away. We recover worms 3-4 times from each vial of soft agar stock. Worms can be frozen in 1.8 ml cryotubes. The CGC uses Nunc Cryotube Vials (#65234) with internal threads and freezes six vials of each strain it receives. Two vials are frozen using Soft Agar Freezing Solution and are stored at −80°C for use as working stocks. Four vials are frozen using Liquid Freezing Solution; one is thawed as a tester, and the other three are put in at least two different liquid nitrogen tanks. To fill strain requests, the working stocks that are kept at −80°C are used. When the last vial of a stock stored at −80°C is emptied, the worms are once again frozen using Soft Agar Freezing Solution in order to replace these vials. In theory, the stocks kept in liquid nitrogen will never need to be used since the soft agar stocks are continually replaced as they are depleted. The recovery of C. elegans from stocks stored in liquid nitrogen is in the range of 35-45% of the total number of animals frozen. This number decreases only slightly after many years of storage in liquid nitrogen. The recovery of stocks stored at −80°C for many years (>10) is not as high as liquid nitrogen, but worms can be safely stored this way for many years (CGC, unpublished data). Of course, a power failure can result in the loss of all stocks kept at −80°C, so it is very wise to keep at least one copy of all stocks in liquid nitrogen. Some mutants strains (especially certain Dpy mutants) do not survive freezing as well as wild-type animals. Protocol 7. Freezing C. elegans using Liquid Freezing Solution Equipment and Reagents S Buffer [129 ml 0.05 M K2HPO4, 871 ml 0.05 M KH2PO4, 5.85 g NaCl] S Buffer (see above) + 30% glycerin (v/v) (autoclave) 1.8 ml cryotube vials Methods Use one large, 2-3 medium, or 5-6 small NGM plates that have lots of freshly starved L1-L2 animals. Wash the plates with 0.6 ml S Buffer for each vial you will freeze. Collect liquid in a sterile test tube. Add an equal volume of S Buffer + 30% glycerin. Mix well. Aliquot 1.0 ml of mixture into 1.8 ml cryovials labelled with strain name and date. Pack the cryovials in a small styrofoam box with slots for holding microtubes or use a commercial styrofoam shipping box. Place the box in a −80°C freezer overnight (or for at least 12 hours). The next day transfer the vials to their permanent freezer locations. Thaw one vial as a tester to check how well the worms survived the freezing (See Protocol 9). Protocol 8. Freezing C. elegans using Soft Agar Freezing Solution Equipment and Reagents S Buffer (see Protocol 6) Soft Agar Freezing Solution [0.58 g NaCl, 0.68 g KH2PO4, 30 g glycerol, 0.56 ml 1 M NaOH, 0.4 g agar, H2O to 100 ml (autoclave)] 1.8 ml cryotube vials Methods Melt Soft Agar Freezing Solution in autoclave or microwave and place in 50°C water bath for at least 15 minutes. Use one large, 2-3 medium, or 5-6 small NGM plates that have lots of freshly starved L1-L2 animals. Wash the plates with 0.6 ml S Buffer for each vial you will freeze. Collect liquid in a covered sterile test tube and place in ice for 15 minutes. Add an equal volume of Soft Agar Freezing Solution to the test tube. Mix well. Aliquot 1 ml of mixture into 1.8 ml cryovials labelled with strain name and date. Pack the cryovials in a small styrofoam box with slots for holding microtubes or use a commercial styrofoam shipping box. Place the box in a −80°C freezer overnight (or for at least 12 hours). The next day transfer the vials to their permanent freezer locations. Take a scoop of frozen mixture from one vial as a tester to check how well the worms survived the freezing (see Protocol 10). Protocol 9. Thawing C. elegans frozen using Liquid Freezing Solution Methods Remove a vial from freezer and allow it to thaw at room temperature until all ice has turned to liquid. Pour the contents onto one large NGM plate with E. coli OP50 lawn. You should see worms wiggling after just a few minutes. After 2-3 days, transfer 10-15 animals individually to separate plates. Allow the animals to reproduce for one generation and score the progeny for correct phenotypes. Protocol 10. Thawing C. elegans frozen using Soft Agar Freezing Solution Methods Remove a vial from −80°C freezer and transfer to a small styrofoam box with slots for microtubes. Work quickly so that the solution in the vial does not thaw. Flame a small scoop or spatula and use it to remove 1/4 - 1/3 ml of the frozen solution. Place solution on a NGM plate with E. coli OP50 lawn. Return vial to −80°C freezer as quickly as possible. You should see worms wiggling after just a few minutes. After 2-3 days, transfer 10-15 animals individually to separate plates. Allow the animals to reproduce for one generation and score the progeny for correct phenotypes
  Following
• Question asked in Plant Nematology
  Open Nematological Societies and Federations
  Afro-Asian Society of Nematologists (AASN) Australian Association of Nematologists (AAN) Brazilian Nematological Society (Sociedade Brasileira d... [more]
  Afro-Asian Society of Nematologists (AASN) Australian Association of Nematologists (AAN) Brazilian Nematological Society (Sociedade Brasileira de Nematologia) (SBN) Chinese Society of Plant Nematologists (CSPN) Egyptian Society of Agricultural Nematology (ESAN) European Society of Nematologists International Federation of Nematology Societies (IFNS) Italian Society of Nematologists (Societa Italiana di Nematologia) (SIN) Japanese Nematological Society (JNS) Nematological Society of India (NSI) Nematological Society of Southern Africa (Nematologiese Vereniging van Suidelike Afrika) (NSSA) Organization of Nematologists of Tropical America (ONTA) Pakistan Society of Nematologists (PSN) Russian Society of Nematologists (RSN) Society of Nematologists (SON)
  By Tariq Javeed · King Saud University
  Following