The Nucleolus: The Most Prominent Nuclear Subdomain
rRNA transcription : by RNA Polymerase I
50% of RNA transcription is the cell is rRNA
Nucleuos in Oocyte
Nuclear Membrane and Nuclear Pore Complex : Gateways between Nucleus and Cytoplasm
Nuclear Membrane: two concentric
membranes separating the perinuclear
Outer nuclear membrane is continuous
with and functionally part of the
Inner nuclear membrane has many
novel transmembrane and peripheral
proteins that anchor the nuclear
lamina and interact with chromatin.
Lipid bilayers of the two membranes
are connected around the nuclear pore
Lamina : a protein meshwork lining the inner surface of the inner nuclear membrane.
Disassembly of the nuclear envelope is a critical aspect of mitosis (and meiosis) in higher
It is also called as ‘GVBD’ (Germinal Vesicle Breakdown) in Oocyte..
Genome Size :4.6Mbp
Genome Size :3100Mbp
Protein Coding Gene :20000-25000
Protein Coding Gene : 4288
Genome Size : 13.8Mbp
Protein Coding Gene : 6604
Genome Size : 140Mbp
Protein Coding Gene : 13525
900X time of genome size
5X times of proteins?
Transposon : Junk DNA? Make up much of genome of higher eucaryote
-Retrotransposon : transcribe as RNA -> Convert RNA into DNA-> inserted back to genome
- LINE(long interspered nuclear elements)
- SINES (short interspersed nuclear elements)
- Is ‘junk DNA’ really junk?
- Junk is not a Trash!
Centromeres : the region where the chromosome becomes attached to the mitotic spindle