BP

GO:0000398

mRNA splicing, via spliceosome

The joining together of exons from one or more primary transcripts of messenger RNA (mRNA) and the excision of intron sequences, via a spliceosomal mechanism, so that mRNA consisting only of the joined exons is produced.

IBA|TAS

BP

GO:0001825

blastocyst formation

The initial formation of a blastocyst from a solid ball of cells known as a morula.

IEA

CC

GO:0005654

nucleoplasm

That part of the nuclear content other than the chromosomes or the nucleolus.

IDA|TAS

CC

GO:0005684

U2-type spliceosomal complex

Any spliceosomal complex that forms during the splicing of a messenger RNA primary transcript to excise an intron that has canonical consensus sequences near the 5' and 3' ends.

IBA

CC

GO:0005686

U2 snRNP

A ribonucleoprotein complex that contains small nuclear RNA U2.

IBA

CC

GO:0005689

U12-type spliceosomal complex

Any spliceosomal complex that forms during the splicing of a messenger RNA primary transcript to excise an intron; the series of U12-type spliceosomal complexes is involved in the splicing of the majority of introns that contain atypical AT-AC terminal dinucleotides, as well as other non-canonical introns. The entire splice site signal, not just the terminal dinucleotides, is involved in determining which spliceosome utilizes the site.

IDA

CC

GO:0071011

precatalytic spliceosome

A spliceosomal complex that is formed by the recruitment of a preassembled U5-containing tri-snRNP to the prespliceosome. Although all 5 snRNPs are present, the precatalytic spliceosome is catalytically inactive. The precatalytic spliceosome includes many proteins in addition to those found in the associated snRNPs.

IBA

CC

GO:0071013

catalytic step 2 spliceosome

A spliceosomal complex that contains three snRNPs, including U5, bound to a splicing intermediate in which the first catalytic cleavage of the 5' splice site has occurred. The precise subunit composition differs significantly from that of the catalytic step 1, or activated, spliceosome, and includes many proteins in addition to those found in the associated snRNPs.

IBA

MF

GO:0000166

nucleotide binding

Interacting selectively and non-covalently with a nucleotide, any compound consisting of a nucleoside that is esterified with (ortho)phosphate or an oligophosphate at any hydroxyl group on the ribose or deoxyribose.

IEA

MF

GO:0044822

poly(A) RNA binding

Interacting non-covalently with a poly(A) RNA, a RNA molecule which has a tail of adenine bases.

IDA