lampbrush chromosom

1. Lampbrush Chromosome And
Their Importance
Presented by :
Panchal Rita C.
M.sc. Sem -1 botany
CBO :- 403
Department Of Life Sciences H.N.G.U., Patan

2. Content
• Introduction
• History
• Importance

3. Introduction
• The lampbrush chromosome were first
observed Salamander Pictures in 1882.
• He Coined the name because the
Chromosomes look like the brushes which
were used for cleaning the glass chimneys
of old fashioned paraffin.

4. History
• They were described in detail in shark oocytes by
R.Ruckert in 1892.Thore(1984) and Burns and
Bottino(1989) preferred the term test tube brush
chromosome for them.
• However due to recent investigation of Gall and
coworkers (1983) the structure of these
exceptionally large side chromosome has been
interpreted in functional terms,i.e., now they are
merely visualized as means of"turning on and
turning" of the genes.

5. Lampbrush Chromosome
• Lampbrush chromosome are intermediate
structures present during the first meiotic
division.
• The lampbrush chromosome occur at the
diplotene stage of meiotic prophase in the
primary oocytes of all animal species both
vertebrates and invertebrates.

7. • Lampbrush chromosome are much larger than the
polytene chromosome of insects.
• Since the lampbrush chromosome are found in the
prolonged diplotene stage of meiotic prophase
they are present in the form of bivalents in which
the maternal and paternal chromosomes are held
together by chiasmata at those sites where
crossing over has previously occurred.

9. • The paired homologues are not condensed as usual
chromosome would be instead, they are very long and
stretched.
• The axis of each homologue consist of a row of
granules or chromosome from which lateral loops
extend.
• Each loop of lampbrush chromosome is found to
perform intense transcription of heterogeneous RNA
molecules.

10. Importance
• Lampbrush chromosome also show the possible
way of the gene amplification which required
during the growth phase of oocytes.
• The lampbrush chromosome loops are used to
studying transcription.

11. Reference
• Cell Biology, Genetics, Molecular Biology,
Evolution and Ecology by : P. S. Verma, V. K.
Agarwal.
https://it.m.wikipedia.org
https://www.slideshare.net

12. THANK YOU