biology

RDH13

RDH13 is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand RDH13 rather than just read about it. In short: Retinol dehydrogenase 13 (all-trans/9-cis) is a protein that in humans is encoded by the RDH13 gene. This gene encodes a mitochondrial short-chain dehydrogenase/reductase, which catalyzes the reduction and oxidation of retinoids.

Key takeaways

RDH13 belongs to biology; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect RDH13 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of RDH13 from memory before moving on to harder problems.

Reference excerpt

Retinol dehydrogenase 13 (all-trans/9-cis) is a protein that in humans is encoded by the RDH13 gene. This gene encodes a mitochondrial short-chain dehydrogenase/reductase, which catalyzes the reduction and oxidation of retinoids. The encoded enzyme may function in retinoic acid production and may also protect the mitochondria against oxidative stress. Alternatively spliced transcript variants have been described.

Gene The human RDH13 gene is on the 19th chromosome, with its specific localization being 19q13.42. The gene contains 12 exons in total.

Structure The analysis of the submitochondrial localization of RDH13 indicates its association with the inner mitochondrial membrane. The primary structure of RDH13 contains two hydrophobic segments, 2–21 and 242–261, which are sufficiently long to serve as transmembrane segments; however, as shown in the present study, alkaline extraction completely removes the protein from the membrane, indicating that RDH13 is a peripheral membrane protein. The peripheral association of RDH13 with the membrane further distinguishes this protein from the microsomal retinaldehyde reductases, which are integral membrane proteins that appear to be anchored in the membrane via their N-terminal hydrophobic segments.

Function RDH13 is most closely related to the NADP+-dependent microsomal enzymes RDH11, RDH12 and RDH14. Purified RDH13 acts on retinoids in an oxidative reductive manner, and strongly prefers the cofactor NADPH over NADH. Moreover, RDH13 is much has much more efficient reductase activity than dehydrogenase activity. RDH13 as a retinaldehyde reductase is significantly less active than that of a related protein RDH11, primarily because of the much higher Km value for retinaldehyde. However, the kcat value of RDH13 for retinaldehyde reduction. arable with that of RDH11, and the Km values of the two enzymes for NADPH are also very similar. Thus, consistent with its sequence similarity to RDH11, RDH12 and RDH14, RDH13 acts as an NADP+-dependent retinaldehyde reductase. RDH13 is localized in the mitochondria, which is different from the other members of this family, as they localize to the endoplasmic reticulum. The exact sequence targeting RDH13 to the mitochondria remains to be established.

Clinical significance RDH13 is part of a subfamily of four retinol dehydrogenases, RDH11, RDH12, RDH13, and RDH14, that display dual-substrate specificity, uniquely metabolizing all-trans- and cis-retinols with C(15) pro-R specificity. The metabolites involved in these reactions are known as retinoids, which are chromophores involved in vision, transcriptional regulation, and cellular differentiation. RDH11-14 could be involved in the first step of all-trans- and 9-cis-retinoic acid production in many tissues. RDH11-14 fill the gap in our understanding of 11-cis-retinal and all-trans-retinal transformations in photoreceptor and retinal pigment epithelial cells. The dual-substrate specificity of this subfamily explains the minor phenotype associated with mutations in 11-cis-retinol dehydrogenase (RDH5) causing fundus albipunctatus in humans.

References

Illustrations

Worked examples

Example 1 — a first encounter with RDH13

Start with the simplest possible case. Write down what RDH13 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to RDH13 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about RDH13 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of RDH13

In research: RDH13 appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses RDH13 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: RDH13 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Genes on human chromosome 19, Human chromosome 19 gene stubs, Proteins, so understanding it makes those chapters shorter.
In everyday life: Look for RDH13 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “RDH13” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study RDH13 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what RDH13 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain RDH13 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is RDH13 in simple terms?

Why does RDH13 matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study RDH13?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on RDH13.