Myxobacteria movementCell Tracking

Tanya KazakovaUniversity of Notre DameAdvisor: Dr. Mark Alber

About Myxobacteria

The myxobacteria are Gram-negative organisms (0.5 x 5-7 mm rods) that are capable of multicellular, social behavior.

In the presence of nutrients, swarms of myxobacteria feed cooperatively. If the food supply is limited, the myxobacteria form aggregates called “fruiting bodies.”

Developmental Cycle for Myxobacteria

COUPLING CELL MOVEMENT TO MULTICELLULAR DEVELOPMENT IN MYXOBACTERIA by Dale Kaiser Nature Reviews Microbiology 1, 45-54 (2003)

Two engines of motility: AA and SS

A+S+

A+S-A-S+

AAdventurous SSocial

Cells move as a groupCells move alone

A-S- cells are unable to swarm or form fruiting bodies.

Two engines of motility (cont)

S-motilityThe pilus extends ahead of a cell, adheres to the fibrils on the cells ahead of it and then retracts, pulling the leading end of the piliated cell forward.

A-motilityCell is pushed by slime secretion.

At any instant, only one end secretes slime and only one end assembles pili.One end cannot do both at the same time.

Scenario

Suppose we have an image produced to exhibit the results of a biology experiment. In most cases, we will have a black and white drawing such as one exhibited on the left.

Goals

General: Get the most information from the

image

Specific:– Track individual cells– Make cell density more obvious– Show the boundaries of expanding front– Get rid of noise

About Scion Image

National Institutes of Health Package

http://rsb.info.nih.gov/nih-image/

Using SI: Options -> Color Tables

8 Grays 8 Grays->Fire 1

Original Image

Fire 1

Example

Cell Tracking Features

MATLAB

Example

Possible Directions for Future Work