Phát triển là quá trình kiểm soát sự biểu hiện gen, quá trình điều hòa phức tạp về cơ chế, cơ bản có 5 mức độ:
1- Sự xoắn của NST (Chromatin Packing) 2- Kiểm soát sự phiên mã (Transcriptional Control) 3- Điều hòa hậu phiên mã (Posttranscriptional) [Nhân tế bào (Nuclear levels)] 4- Kiểm soát sự giải mã (Translational Control) 5- Điều hòa hậu giải mã (Posttranslational Control) [Cytosol (Cytoplasmic levels)]
Sự điều hòa phiên mã bởi những phân tử protein,yếu tố phiên mã (transcription fact...
Alterations in chromatin packing are not the only
physical manifestations of cancer. A cluster of tumour
cells will also usually display gross structural changes
that pathologists use for diagnosis: cells look visibly
deformed and are often enlarged, with swollen and
misshapen nuclei; and the chromosomes are distri-
buted eccentrically. In an attempt to study these chan-
ges more accurately, researchers at ASU’s Biodesign
Institute have developed an optical computerized
tomography (CT) scan for individual cells.
are there breast cancer cells
in your lymph nodes?
Your doctor will examine your lymph
nodes to see if they contain cancer.
Having cancer cells in the lymph nodes
under your arm is associated with an
increased risk of the cancer spreading.
Lymph nodes are filters along the lymph
fluid channels. Lymph fluid leaves the
breast and eventually goes back into the
bloodstream. The lymph nodes try to
catch and trap cancer cells before they
reach other parts of the body.
When lymph nodes are free, or clear,
of cancer, the test results are called
In this chapter, students will be able to understand: Chromatin structure is based on successive levels of DNA packing; gene expression can be regulated at any stage, but the key step is transcription; cancer results from genetic changes that affect cell cycle control;...