Cheung Lab, Days 5 and 6


Leaf discs after being transferred to new medium

This week was a hectic one with my Nanotechnology Class, but I was still able to work in the lab a couple of days, Monday and Friday.  It was similar to other processes that we completed earlier, so it was relatively easy on the “learning” side.

On Monday, we dipped more Arabidopsis plants with 3 different bacterial lines.  When I got to the lab, the plants were already cleaned, so it was as easy as spinning down the bacteria, preparing the solutions, and actually dipping the buds.  We then tied up the plants we had dipped the previous week.


Tied Arabidopsis plants

On Friday, we worked on transferring the tobacco leaf discs from their medium to a new medium; one that induced shoots to grow and selected for antibacterial resistance.  The process was simple- consolidating 3 plates from the previous medium to 2 plates of the new medium.  After transferring the plates, we looked at our direct-soil germinated plants, and spread them out evenly in each plant pot.



Sorting soil-germinated plants

Cheung Lab, Day 4


Arabidopsis prepped for dipping with Agrobacterium

On Day 4, our final day of the first week, we finished up learning about transformation methods.  We had a four day week because yesterday was July 4th, and the lab was closed to celebrate the holiday!

We started out the day by transferring our leaf-discs from co-cultivation medium with Agrobacterium to SIM-which is used to grow shoots.  The Agrobacterium were washed off of the leaf discs, using B5- which is basic growth medium.  We completed 3 washes to basically dilute the bacterium to a very low level.  The discs will stay in this medium for about a week.


Plates in the 22 degree Celsius growth chamber

We moved our plates to the growth chamber in the basement of Lederle Graduate Research Tower.  The plates will grow in the chamber for a while.

We then started a new process of transformation, this time using Arabidopsis.  The method we used was transformation by dipping.  Basically, you take the unopened buds, and dip them in a solution of agrobacterium.  This solution will change some of the seeds.  You then screen the next generation, find the modified seeds, and grow them into plants, which produce a new generation of modified seeds.


Mixing Agrobacterium on an orbit shaker.

Alice Cheung’s Lab, Day 2


Our seeds, which will be ready in about five weeks.

Today, we started out the day by editing the procedure, which was different than the actual procedure that I described yesterday (and that lab members have taught us.)  We started by doing a seed screening, this time with many different genes, which we will compare in five weeks on the young plants.  The genes we were investigating were RK10p:Gus, RK11p:Gus, Wildtype (Normal) Arac7p:Gus, And Arac10p:Gus

We then prepared soil and spread seeds for direct soil germination.  There is a lab protocol for exactly how the soil is supposed to made, which was very interesting to learn (and remember well from my childhood.


A solution of nutrients to be mixed with the soil.


Our seeds are covered so that the soil doesn’t get too dry, but have a corner propped to help mitigate mold growth.