Related Experiment Video
Updated: May 19, 2026
10:23
Analysis of Epididymal Protein Synthesis and Secretion
Published on: August 25, 2018
Testicular and epididymal ADAMs: expression and function during fertilization
1School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea. choch@gist.ac.kr
Nature Reviews. Urology
|August 29, 2012
Summary
Reproductive ADAM proteins are crucial for male fertility. The ADAM2-ADAM3 complex, essential for sperm migration, highlights the importance of these proteins in male reproduction.
Area of Science:
- Reproductive biology
- Molecular and cell biology
- Biochemistry
Background:
- The ADAM (a disintegrin and metalloprotease domain) protein family includes over 34 multidomain membrane proteins in mammals.
- Over half of these ADAM proteins are primarily found in the testes and epididymis, suggesting a significant role in male reproductive functions.
- Reproductive ADAMs are categorized into three distinct phylogenetic groups (I, II, and III), each with unique characteristics.
Purpose of the Study:
- To investigate the structural and functional diversity of reproductive ADAM proteins.
- To explore the specific roles of different ADAM groups and their complexes in male reproduction.
- To elucidate the critical functions of ADAM2 and ADAM3 in sperm biology and fertilization.
Main Methods:
- Phylogenetic analysis to classify reproductive ADAM proteins into groups I, II, and III.
- Analysis of gene structure (introns/exons) and protein processing in mature sperm.
- Identification of ADAM protein complexes on sperm surfaces.
- Utilizing mouse knockout models to assess the in vivo function of specific ADAM complexes.
Main Results:
- Group I ADAMs (11 proteins) are testicular, with intronless genes and often lack prodomains in mature sperm.
- Group II ADAMs (5 proteins) are expressed in germ cells, lacking both prodomains and metalloprotease domains in mature sperm.
- Group III ADAMs (2 proteins) are synthesized in the epididymis, with one secreted to the sperm surface, and ADAM2-ADAM3 complex is vital for sperm migration.
Conclusions:
- Reproductive ADAM proteins exhibit significant diversity in structure, expression, and processing, reflecting specialized roles in male reproduction.
- The ADAM2-ADAM3 complex is indispensable for sperm motility and successful navigation within the female reproductive tract.
- Further research into ADAM proteins can offer insights into male infertility and potential contraceptive strategies.
Related Concept Videos
01:27Testes: Histology
A tough, fibrous membrane, the tunica albuginea, covers the testes, extending inward to form fibrous partitions or septa, dividing them into internal compartments called lobules. Each lobule has 1 to 3 tightly coiled seminiferous tubules where sperm production occurs. These tubules merge into a tubular network at the back of the testis, known as the rete testis. It connects to 15 to 20 efferent ductules, leading to the epididymis.
The spermatogenic cells, responsible for producing sperm, are...
The spermatogenic cells, responsible for producing sperm, are...
01:15Sperm Transport
The journey of sperm from its origin to the point of ejaculation begins within the seminiferous tubules of the testis. Here, Sertoli cells produce fluid that propels non-motile sperm through a series of conduits, starting with the straight tubules leading to the rete testis. This interconnected network of tubules acts as the initial pathway for sperm, guiding them into the efferent ductules and then into the epididymis for maturation.
The maturation phase occurs in the epididymis, where sperm...
The maturation phase occurs in the epididymis, where sperm...
01:19Testes: Gross Anatomy
The testes, also known as testicles, are the male gonads. They are housed within the scrotum, a sac-like structure located beneath the penis. The scrotum's primary role is to regulate the temperature of the testes, which is crucial for sperm production.
Each testis is surrounded by the tunica albuginea, a dense connective tissue layer that provides structural support and protection. This layer is covered by an outer serous membrane called the tunica vaginalis, which helps reduce friction...
Each testis is surrounded by the tunica albuginea, a dense connective tissue layer that provides structural support and protection. This layer is covered by an outer serous membrane called the tunica vaginalis, which helps reduce friction...
01:16Accessory Glands of the Male Reproductive System
The accessory ducts involved in sperm maturation and transportation include the epididymides, vasa deferentia, ejaculatory ducts, and urethra. These ducts play a critical role in the maturation, storage, and transportation of sperm from the testes to the urethra, where it is then released during ejaculation.
The epididymis is a small, comma-shaped organ located at the back of each testicle. The epididymis can be divided into three main parts: the head, body, and tail. The head of the epididymis...
The epididymis is a small, comma-shaped organ located at the back of each testicle. The epididymis can be divided into three main parts: the head, body, and tail. The head of the epididymis...
01:15Development of the Sexual Organs in the Embryo and Fetus
Development of the reproductive organs in an embryo starts from a bipotential state. This means the early embryo can develop either male or female reproductive organs. The formation of these organs begins with the growth of gonadal ridges that arise from the intermediate mesoderm during the fifth week of development.
Near the gonadal ridges, two duct systems are present: the mesonephric ducts (Wolffian ducts) and paramesonephric ducts (Müllerian ducts). These ducts form the basis for the male...
Near the gonadal ridges, two duct systems are present: the mesonephric ducts (Wolffian ducts) and paramesonephric ducts (Müllerian ducts). These ducts form the basis for the male...
01:41Spermatogenesis
Spermatogenesis is the process by which haploid sperm cells are produced in the male testes. It starts with stem cells located close to the outer rim of seminiferous tubules. These spermatogonial stem cells divide asymmetrically to give rise to additional stem cells (meaning that these structures “self-renew”), as well as sperm progenitors, called spermatocytes. Importantly, this method of asymmetric mitotic division maintains a population of spermatogonial stem cells in the male reproductive...