Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of the vertebrate eye, which function to maintain the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystallins are made and then retained throughout life, making them extremely stable proteins. Mammalian lens crystallins are divided into alpha, beta, and gamma families; beta and gamma crystallins are also defined as a superfamily. Alpha and beta families are further divided into acidic and basic groups. Seven protein regions exist in crystallins: four homologous motifs, a connecting peptide, and N- and C-terminal extensions. Beta-crystallins, the most heterogeneous, differ by the presence of the C-terminal extension (present in the basic group but absent in the acidic group). Beta-crystallins form aggregates of different sizes and are able to form homodimers through self-association or heterodimers with other beta-crystallins. This gene is a beta acidic group member. Three alternatively spliced transcript variants encoding identical proteins have been reported. [provided by RefSeq, Jul 2008]
Transcription factors with Perturb-seq knockdown data for CRYBA2. The Binding column indicates whether any binding evidence exists for this TF–gene pair (ChIP-seq or motif footprint peaks). The Mean coef is the average Perturb-seq regression coefficient across active gRNAs (positive = CRYBA2 upregulated upon KD; negative = downregulated). The Outlier column indicates whether this gene is in the top or bottom 5% of all TF knockdown effects.
| TF | Mean coef | Binding | Outlier | TF→Gene link |
|---|
Open chromatin peaks (ATAC-seq) in the genomic neighbourhood of CRYBA2, linked by TSS proximity or chromatin conformation (Multiome / HiCAR). Each element overlaps at least one TF ChIP-seq binding site — the TFs column shows how many distinct TFs bind that element.
| Accessibility | Element | Dist. to TSS | Link type | TFs |
|---|---|---|---|---|
| chr2:218,984,382–218,985,013 | 8.4 kb | Proximal (<10kb) | 126 | |
| chr2:218,992,930–218,994,312 | at TSS | At TSS | 265 | |
| chr2:218,995,885–218,998,018 | 2.5 kb | Proximal (<10kb) | 534 | |
| chr2:218,998,611–219,003,562 | 5.2 kb | Proximal (<10kb) | 941 |
Genomic view of the CRYBA2 locus showing ATAC-seq accessibility and RNA-seq expression across the ESC → DE time course, together with TF binding peaks and element-to-TSS loop connections.