Y chromosome functions in mammalian spermatogenesis
- Sex Chromosome Biology Laboratory, The Francis Crick Institute, United Kingdom
Figures
Figure 1
Evolution of the eutherian sex chromosomes.
The X and Y chromosomes evolved from a pair of autosomes. First, the testis-determining gene Sry evolved on the proto-Y. Then, successive stratification events occurred, wherein X-Y meiotic …
Figure 2
Gene content and structure of the mouse and human Y chromosome.
The short arm of the mouse Y chromosome (Yp) has retained ancestral non-ampliconic genes. The mouse Y chromosome long arm (Yq) contains alternating tandem and palindromic repeats of ampliconic core …
Figure 3
Mammalian spermatogenesis in seminiferous tubules of the testis.
Spermatogenesis occurs in three main phases: mitosis, meiosis and spermiogenesis. First, undifferentiated spermatogonial cells undergo multiple mitotic divisions. Subsequently, germ cells commit to …
Figure 4
Y-linked gene complements and developmental progression through spermatogenesis.
Specific Y genes control the developmental progress of germ cells in spermatogenesis. The presence of the Y short arm (Yp) allows formation of sperm which have abnormal heads, exhibiting reduced …
Tables
Table 1
Dosage compensation of the sex chromosomes.
Without dosage compensation, the transcriptional output of each cell is 0.5 for individual chromosomes, and one for chromosome pairs. X-chromosome upregulation (XCU) doubles each X-chromosome’s …
| No compensation | XCU | XCI | |
|---|---|---|---|
| female | AA = 1XX = 1 | AA = 1 = 2 | AA = 1 = 1 |
| male | AA = 1XY = 0.5 | AA = 1Y = 1 | AA = 1Y = 1 |
Table 2
Summary of mouse Y chromosome genes and their known functions.
A gene is classified as ‘ancestral’ if it is predicted to have been present in the last common eutherian ancestor. The list of animals where each gene is conserved only includes organisms where a …
| Y gene | Sequence class | X-homologue | Y copy number | Conserved in | Reported functions in the testis | Key gene ontology process | Expression pattern |
|---|---|---|---|---|---|---|---|
| Sry | Ancestral | Sox3 | 1 | Opossum, bull, rat, mouse, marmoset, rhesus, chimp, human | Testis determination | DNA-binding transcription factor activity | Somatic cells in genital ridge, germ cell specific in adult |
| Rbmy array | Ancestral | Rbmx | ~30 | Opossum, bull, rat, mouse, marmoset, rhesus, chimp, human | Unknown * | RNA splicing | Testis biased |
| Zfy1,Zfy2 | Ancestral | Zfx | 2 | Bull, rat, mouse, marmoset, rhesus, chimp, human | Apoptotic elimination of univalent spermatocytes at metaphase I, meiosis II completion, MSCI initiation and maintenance, spermatid head and tail morphogenesis | Transcription activator | Spermatogenic cells specific |
| Kdm5d | Ancestral | Kdm5c | 1 | Opossum, rat, mouse, marmoset, rhesus, chimp, human | Unknown | Histone demethylase that specifically demethylates 'Lys-4' of histone H3 | Ubiquitous |
| Uty | Ancestral | Utx | 1 | Bull, rat, mouse, marmoset, rhesus, chimp, human | Unknown | Histone demethylase activity (H3-K27 specific) | Ubiquitous |
| Ddx3y | ancestral | Ddx3x | 1 | Bull, rat, mouse, marmoset, rhesus, chimp, human | Unknown | ATP-dependent RNA helicase | Ubiquitous |
| Usp9y | Ancestral | Usp9x | 1 | Bull, rat, mouse, marmoset, rhesus, chimp, human | Unknown | Ubiquitination regulator, peptidase C19 | Testis biased |
| Uba1y | Ancestral | Uba1x | 1 | Opossum, bull, rat, mouse | Unknown | U1 ubiquitin activator | Testis biased, mostly spermatogonia and round spermatid |
| Eif2s3y | Ancestral | Eif2s3x | 1 | Bull, rat, mouse | Spermatogonial proliferation and differentiation | Translation initiation | Ubiquitous |
| Teyorf | Acquired | – | 1 | Mouse | Unknown | Claudin transmembrane | Testis specific |
| Prslly | Acquired | – | 1 | Mouse | Unknown | Serine-type endopeptidase activity | Testis specific |
| H2al2b, H2al2c | Acquired | H2al1 | 2 | Mouse | Unknown | DNA packaging, pericentric heterochromatin regulation | Testis specific, expressed from round spermatid stage |
| Sly | Acquired | Slx,Slxl1 | 126 | Mouse | Interacts with SSTY to recruit SMRT/N-Cor in turn mediating spermatid-specific gene expression | Chromatin remodelling | Testis biased |
| Srsy | Acquired | Srsx | 197 | Mouse | Unknown | Unknown | Testis biased |
| Ssty1&2 | Acquired | Sstx | 85&221 | Mouse | H3K4me3-reader at the promoter of spermatid-specific genes, recruits SLY and SLX/SLX1 | Methylated histone binding | Testis biased |
| Rbm31y | Acquired | Rbm31x | 2 | Mouse | Unknown | RNA binding | Testis biased |
