Related Experiment Video
Updated: Jun 25, 2026
05:58
Site-Specific Lysine Lactylation via Genetic Code Expansion in E. coli and Mammalian Cells
Published on: February 24, 2026
Decoding the enhancer-driven regulatory network for lactoferrin across mammalian species.
Hui-Mei Fan1,2, Yu-Yi Lu1,2, Zhen-Yu Wei1,2
1Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi 712100, China.
Zoological Research
|June 24, 2026
Summary
Researchers uncovered the regulatory mechanisms controlling lactoferrin (LTF) expression in mammary glands. They identified key enhancers and transcription factors crucial for LTF production, offering insights into mammary gland health and milk quality in dairy cattle.
Area of Science:
- Genomics
- Molecular Biology
- Mammalian Physiology
Background:
- Lactoferrin (LTF) is a vital milk protein involved in immunity and iron regulation.
- The precise genetic regulation of LTF in mammary glands is not fully understood.
Purpose of the Study:
- To elucidate the regulatory landscape and evolutionary aspects of mammalian LTF expression.
- To identify key genetic elements and transcription factors controlling LTF in mammary tissues.
Main Methods:
- Integrated multi-omics data and comparative genomics.
- Performed cross-tissue and single-cell transcriptomic analyses.
- Conducted correlation analysis in Holstein cows and functional validation of enhancers.
Main Results:
- LTF expression is highest in salivary and mammary glands, specifically in secretory luminal epithelial cells.
- Identified three functional enhancers, two of which are ruminant-specific and conserved.
- Discovered EHF and ELF5 transcription factors directly regulate LTF via these enhancers.
- A human enhancer significantly boosts LTF expression and retains activity in bovine cells.
Conclusions:
- Established an evolutionarily diverse regulatory framework for lactation-specific LTF expression.
- Identified candidate regulatory elements and transcription factors for improving mammary gland health and LTF content in dairy cattle.
Related Concept Videos
01:25Inducible Operons: lac Operon
The lac operon in Escherichia coli is a model for understanding inducible gene regulation and metabolic flexibility. It integrates local control by lactose and global regulation through catabolite repression, enabling E. coli to preferentially metabolize glucose when available and switch to lactose utilization when glucose is scarce.Structure and Function of the lac OperonThe lac operon contains three structural genes: lacZ (β-galactosidase), lacY (lactose permease), and lacA (thiogalactoside...
02:09Operons
Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by a repressor...
01:23Operon Model
The operon model represents a fundamental mechanism of gene regulation in prokaryotes, enabling coordinated expression of genes involved in related metabolic or functional pathways. Operons consist of structural genes, a promoter, and an operator, with transcription regulated by repressors, activators, and small effector molecules.Structure and Function of OperonsAn operon is a cluster of structural genes transcribed together under the control of a single promoter. The promoter region...
01:58Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
01:58Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
02:23Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...