Replication-dependent histone mRNAs are not polyadenylated; instead their 3' end is formed by a single endonucleolytic cleavage between a conserved stem-loop and a purine-rich histone downstream element. The stem-loop binding protein (Slbp) binds the stem-loop, and the U7 snRNP, whose U7 snRNA base pairs with the downstream element and whose Sm ring contains the U7-specific Lsm10 and Lsm11, recruits FLASH and the histone pre-mRNA cleavage complex. This complex reuses the Cpsf73 endonuclease, Cpsf100 and Symplekin together with other CPSF and CstF subunits. In Drosophila these factors concentrate in the histone locus body.
Boundary. FlyBase's HPF group is the union of HCC, U7 and Slbp plus FLASH, and all members are covered by the four parts. The histone pre-mRNA cleavage complex shares all its subunits with the polyadenylation machinery in dmel_cleavage_polyadenylation. The core Sm proteins of the U7 snRNP (SmB, SmD3, SmE, SmF, SNRPG) are shared with spliceosomal snRNPs. snRNA:U7 has no protein product and is grounded to its FlyBase gene id. FlyBase groups realized by this module: HCC (FBgg0000615), U7 (FBgg0000628), HPF (FBgg0000630). Participants were generated from the FlyBase gene-group membership and mapped to UniProtKB by projects/FLYBASE_GENE_GROUPS/generate_modules.py from module_specs/dmel_histone_mrna_3prime_processing.yaml. Genes without a usable UniProtKB entry are grounded to their FlyBase gene ids: snRNA:U7. None of the member genes has a gene review in this repository yet.
All recommended fields populated.
✗ none found
No MODULE:dmel_histone_mrna_3prime_processing deep-research report alongside the module YAML.
✓ every leaf node grounds to a representative protein.
✓ every declared conforms_to bundle matches its template motif.
0 gene-function check(s) reflected in core functions · 0 conflict(s) · 2 evidence or coverage gap(s) (2 comparison(s))
Retained noncore functions are reported separately; they do not require promotion to core functions. Support from representative genes does not establish conservation across the whole family. Missing reviews or identifiers leave a claim unverified.
| Annoton | Participant | Function | Assessment |
|---|---|---|---|
| stem_loop_binding_slbp | Slbp UniProtKB:Q9VAN6 Gene |
histone pre-mRNA stem-loop binding GO:0071207 |
Review Missing
No ai-review exists for this protein; its function and core-function coverage cannot yet be checked. |
| histone_cleavage_complex_complex/cpsf73 | Cpsf73 UniProtKB:Q9VE51 Complex Unit |
RNA endonuclease activity GO:0004521 |
Review Missing
No ai-review exists for this protein; its function and core-function coverage cannot yet be checked. |
0 complete review(s) · 0 with deep research · 19 missing review · 0 reviewed but lacking deep research
| Gene | Review | Complete | Deep research |
|---|---|---|---|
| Lsm11 A1Z802 | ✗ | — | — |
| Lsm10 A1Z8C4 | ✗ | — | — |
| FLASH A4UZF6 | ✗ | — | — |
| SmD3 O44437 | ✗ | — | — |
| su(f) P25991 | ✗ | — | — |
| SmB Q05856 | ✗ | — | — |
| SmF Q24297 | ✗ | — | — |
| Sym Q8MSU4 | ✗ | — | — |
| Cpsf100 Q9V3D6 | ✗ | — | — |
| Cpsf160 Q9V726 | ✗ | — | — |
| CstF50 Q9V9V0 | ✗ | — | — |
| Slbp Q9VAN6 | ✗ | — | — |
| Cpsf73 Q9VE51 | ✗ | — | — |
| CstF64 Q9VE52 | ✗ | — | — |
| SmE Q9VLV5 | ✗ | — | — |
| Fip1 Q9VN31 | ✗ | — | — |
| Wdr33 Q9VNG2 | ✗ | — | — |
| Clp Q9VPT8 | ✗ | — | — |
| SNRPG Q9VXE0 | ✗ | — | — |
Slbp, the U7 snRNP, FLASH and the histone pre-mRNA cleavage complex, which cut histone pre-mRNAs after the stem-loop.