Committed to providing comprehensive support for global drug development

Thyroid hormone receptors (TRs) belong to the nuclear receptor superfamily and serve as key molecules mediating the biological functions of thyroid hormones (T3/T4). By regulating the transcription of target genes, they participate in metabolism, growth and development, and tissue homeostasis. TRs exist in two subtypes—TRα and TRβ—and the proteins they encode contain a DNA-binding domain (DBD) and a ligand-binding domain (LBD).

Thyroid Hormone Receptor Alpha (THRA, or TRα) is a member of the nuclear receptor superfamily. As one of the primary receptors for thyroid hormones (T3/T4), it plays a dominant role in the physiological regulation of the heart, skeletal muscle, and the central nervous system. It typically binds to the promoters of target genes either as a homodimer or as a heterodimer formed with the Retinoid X Receptor (RXR). Compared to THRB (Thyroid Hormone Receptor Beta), THRA is highly expressed during embryonic development, where it regulates cardiac development (e.g., myocardial contractility), skeletal maturation, and central nervous system plasticity. Under pathological conditions, abnormal THRA function is associated with various diseases, including thyroid hormone resistance syndrome, cardiovascular diseases, and metabolic disorders.

The THRA Luciferase Reporter HEK293 cell line consists of HEK293 cells in which the expression of a luciferase reporter gene is regulated by THRA. Thyroid hormones (T3/T4) are potent hormones that exert their effects primarily by binding to TRs, thereby regulating gene expression and cellular function. The underlying principle is illustrated in the figure below.

Figure 1. Schematic Diagram of the THRA Luciferase Reporter HEK293 Mechanism

Figure 2. WB of  hTHRA Luciferase Reporter HEK293.

Figure 3. Dose Response of T3 in THRA Luciferase Reporter HEK293.

Cell Resuscitation
1)Rapidly thaw the frozen cells in a 37 °C water bath for approximately 60 seconds. Once thawed (which may take slightly less or more than 60 seconds), immediately transfer the cell suspension from the cryovial into a 15 mL centrifuge tube containing 10 mL of pre-warmed HEK293 Human THRA Luciferase Reporter Cell complete culture medium.
2)Centrifuge cells at 1000 rpm for 5 min to remove medium, then resuspend cells in 5 mL of pre-warmed complete medium.
3)Transfer the cell suspension into a T25 culture flask and incubate at 37 °C with 5% CO₂.
4)After approximately 24–36 hours, replace the medium or passage the cells to remove non-adherent dead cells.

Subculturing procedure
1)When the cell density reaches the appropriate confluency for passaging, wash the cells with PBS, then add 1 mL trypsin to detach the cells. When more than 80% of the cells detach upon gently tapping the culture flask, add complete culture medium to terminate digestion. Gently pipette to obtain a single-cell suspension, transfer to a 15 mL centrifuge tube, and centrifuge at 1000 rpm for 5 minutes.

2)Discard supernatant after centrifugation. Resuspend cells in fresh medium to a single-cell suspension and transfer to a new culture flask for continued growth.

Cell Freezing
After trypsinization and centrifugation of cells from each T75 flask or 10 cm culture dish, discard the supernatant. Add 2 mL of cryopreservation medium (90% FBS + 10% DMSO), gently resuspend thoroughly, and aliquot into two cryovials. Immediately place the cryovials into a controlled-rate freezing container (e.g., Nalgene 5100-0001), fill with isopropanol to the indicated level, and store at −80 °C. After 24 hours, transfer the cryovials to liquid nitrogen for long-term storage.