Zinc finger Y-chromosomal protein is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

that in humans is encoded by the ''ZFY''

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

of the

Y chromosome The Y chromosome is one of two sex chromosomes in therian mammals and other organisms. Along with the X chromosome, it is part of the XY sex-determination system, in which the Y is the sex-determining chromosome because the presence of the ...

. This gene encodes a

zinc finger A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) which stabilizes the fold. The term ''zinc finger'' was originally coined to describe the finger-like appearance of a ...

-containing protein that may function as a

transcription factor In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription (genetics), transcription of genetics, genetic information from DNA to messenger RNA, by binding t ...

. This gene was once a candidate gene for the testis-determining factor (TDF) and was erroneously referred to as TDF. Humans express a single ZFY gene with two splice variants, while mice express two paralogous copies, Zfy1 and Zfy2. During

spermatogenesis Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testicle. This process starts with the Mitosis, mitotic division of the stem cells located close to the basement membrane of ...

, wrongful expression of either Zfy1 or Zfy2 results in programmed cell death,

apoptosis Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...

, at the mid-pachytene checkpoint. In mice, Zfy genes are necessary for meiotic sex chromosome inactivation (MSCI). In Zfy knockout spermatocytes,

sex chromosome Sex chromosomes (also referred to as allosomes, heterotypical chromosome, gonosomes, heterochromosomes, or idiochromosomes) are chromosomes that carry the genes that determine the sex of an individual. The human sex chromosomes are a typical pair ...

s are incorrectly silenced. Thus, Zfy performs three functions at the mid-pachytene checkpoint: (1) promote MSCI, (2) monitor MSCI progress, and (3) execute cells, via apoptosis, that fail to undergo MSCI. In humans, ZFY is broadly expressed across tissues with particularly high expression in the

testis A testicle or testis ( testes) is the gonad in all male bilaterians, including humans, and is Homology (biology), homologous to the ovary in females. Its primary functions are the production of sperm and the secretion of Androgen, androgens, p ...

. Disorders associated with the ZFY gene include campomelic dysplasia, cystadenofibroma, and Frasier syndrome.

References

Further reading